M&M Home Remodeling Services

Roofing, Gutters, Siding,

About us

M&M is a provider and installer of a broad line of home exterior products including Roofing, Windows, Entry Doors, Siding, Soffit, Fascia and Gutters. Since its formation, M&M has fostered a culture of putting customer satisfaction first, providing quality products and service, competitive pricing and taking the guess-work and worry out of the home improvement process. Celebrating over 37 years of quality, the bulk of M&M business consistently results from customer referrals. M&M accreditation's include the Better Business Bureaus of Chicago and NW Indiana, Owens Corning Platinum Preferred Contractor and the National Association of the Remodeling Industry. M&M has built its reputation as a solutions provider, offering quality products, service, competitive pricing and customer-friendly financing programs .

Business highlights

48 years of trusted experience
Se Habla Español
Family Owned & Operated

Services we offer

Roofing, Windows, Entry Doors, Siding, Soffit, Fascia, Gutters

Amenities

Free Estimates
Yes
Warranties
Yes
Senior Discount

5%



Accepted payment methods

American Express
Check
Discover
Financing Available
MasterCard
Visa


Photos of past projects

Reviews

4.5148 Reviews
Number of StarsImage of DistributionNumber of Ratings
5
66%
4
11%
3
5%
2
5%
1
13%


Rating CategoryRating out of 5
quality
4.5
value
4.3
professionalism
4.5
responsiveness
4.4
punctuality
4.6

Filter reviews by category

Showing 51-75 of 148 reviews

Lawrence M.
03/2014
5.0
roofing, replacement windows, doors
  + 1 more
They came out and did an estimate. They were professional and would use them again in the future. They did the repair work and didn't try to take me for more money.
Description of Work: New windows, doors and roof repair.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$78,000

Response from M&M Home Remodeling Services
Thank you for choosing M&M to help you with your home remodeling needs and thank you for taking the time to let us know how we did. If there is anything else we can help you with please let us know!

Blenda R.
03/2014
5.0
roofing
  + -1 more
Consultation was pleasant that the price was more than fair. I had spoke with most of the big name roofers in the area and their price was close or better. The warranty and the 5 year inspection was also an important selling factor. Overall I am pleased they actually came out and in one day tore-off my old roof and installed the new one with debris left.
Description of Work: New shingle roof with tear-off.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$8,500

Response from M&M Home Remodeling Services
Thank you for letting us know how we did, it's important to us that our customers are happy with our services. If you have any issues or need anything else don't hesitate to give us a call, we would be happy to go out and meet with you again!

Curt H.
02/2014
1.0
roofing
  + -1 more
Contacted the provider to get an estimate for re-roof. Got a salesman that showed up, handed me a brochure, and told me they needed to take aerial photographs to give me a quote. They never provided me a quote. I had hope to use them for a master bath remodel, but after this experience, I don't trust them one bit...
Description of Work: Came out for a quote for re-roof and never responded...

Rating CategoryRating out of 5
professionalism
1.0
responsiveness
1.0
punctuality
1.0


Response from M&M Home Remodeling Services
I wanted to take a moment to say we here at M&M Home Remodeling Services are sorry your experience with us was not as you had hoped. We certainly appreciate your considerations with our company. Please allow me the opportunity to explain what I discovered as I researched your comments along with our records of the appointment you had with an M&M sales rep. The sales rep that you were assigned is a long time representative of our company, one who always treats customers with great respect and gives them the best professional experience they deserve. Part of that experience is to not cut corners in our normal operating procedures. I realize you expected a quote on the day of your appointment, however it is not always possible to deliver one that day due to certain circumstances. Our rep truly felt it best to follow procedures and verify his findings before presenting a price. In addition our sales rep was waiting for you to confirm your work schedule and get back to him so that we could meet with you again for the proper solution to your roofing concerns. According to the notes in our customer tracking system we have not heard back from you which did not allow us to give you the quality service you deserve. It would be my great pleasure to assist you with your roofing concerns if they have not been addressed yet and your bathroom as well. If you are interested I would like to speak with you personally so that I can make sure your next experience is better than your first. Thank you again for considering M&M Home Remodeling Services for your interior and exterior home needs. Jim Martin Operations Manager M&M Home Remodeling Services jmartin@m-mcorp.com (708) 941-7900

Julie E.
01/2014
5.0
roofing
  + -1 more
Jeremy was completely professional - he explained the process and options fully and answered all my questions - even the questions I had after he left. He responded to my queries quickly. When I came home that evening, other than a new roof, there was no trace of all the work that had gone on that day. They cleaned up completely.
Description of Work: Complete tear off and replace house roof, built saddle by fireplace, tore off and replaced flat room on front porch

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$6,100

Response from M&M Home Remodeling Services
Thank you for giving us your feedback. We appreciate the time you took from your day to let us know how we are doing. If there is anything else you need us to do please don't hesitate to give us a call.

Barbara N.
12/2013
5.0
roofing
  + -1 more
They were very good and efficient and left everything in good order.
Description of Work: They repaired some gutters and roofing.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
4.0
punctuality
4.0

Yes, I recommend this pro

Response from M&M Home Remodeling Services
Thank you for your feedback, we appreciate you taking the time to let us know how we did. Please keep us in mind for any other remodeling work you might need.

Jim M.
12/2013
5.0
roofing
  + -1 more
They replaced a small roof on our related living house. They did an amazing job and the crew was wonderful. Even the children commented on how respectful everyone was. Great job! | |Josephine Tamborrino
Description of Work: They replaced a small roof on our related living house. They did an amazing job and the crew was wonderful. Even the children commented on how respectful everyone was. Great job! | |Josephine Tamborrino

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$2,500

Jan B.
12/2013
5.0
replacement windows
  + -1 more
Replaced 5 windows. It all went smoothly from the sales presentation to the installation. The installation was done on schedule. Everyone was professional and efficient. I'm happy with the results.
Description of Work: I used M&M Home Remodeling Services

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$2,300

Response from M&M Home Remodeling Services
Thank you for taking time out of your day to let others know how we did. Hope those windows are keeping you warm in this cold chilly weather. Let us know if there is anything else we can help you with.

Ronald S.
12/2013
5.0
gutter repair, roofing
  + 0 more
The work crews arrived on time every day, and were very professional and polite. They were especially helpful in figuring out unique solutions to problems that were the result of some unusual design features in my older home. They were also extremely conscientious in cleaning up after each day's work, leaving my yard cleaner than it was before they actually started! At the finish of each day's work, the sales estimate coordinator and the project manager stopped by the job site to inspect the progress, and to ensure that I was satisfied with the workmanship. When I received my final bill, everything was itemized and exactly as expected. I would not hesitate to recommend M & M for any type of roofing, soffit, fascia, and rain gutter installation.
Description of Work: Removed old leaking roof and gutters, replaced rotting portions of roof deck and fascia boards, and installed new roof, aluminum soffit and facia covering, rain gutters with Perma Flow leaf guard, and oversize downspouts.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$15,000

Response from M&M Home Remodeling Services
Thanks you for taking the time to let us know how we are doing. Please let us know if there is anything else we can do for you!

Ernestine B.
10/2013
5.0
siding
  + -1 more
They were very sharp and never were late. They worked really well, I had never seen anyone work as hard as them. The supervisor came by everyday. I would like to recommend them. It's like I have a whole new house on the block. Markel Ferrel was the sales person and supervisor and he did just a great job. The office staff has called me afterward to make sure that everything was alright.
Description of Work: They put in all new siding

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$21,626

Response from M&M Home Remodeling Services
Thank you for such wonderful feedback! We really appreciate you taking the time to let us know how we did. And remember we are here if you have any issues or need our help on another project!

Argena A.
09/2013
5.0
doors
  + -1 more
They were efficient. They were on time. They got the paperwork to me straight away.
Description of Work: I used M&M Home Remodeling Services for doors. I am going to use them. They were pretty friendly. I got a quote from them. I got a quote from them in July. It took awhile for me to get approval from the board.

Rating CategoryRating out of 5
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro

Response from M&M Home Remodeling Services
Thanks so much for taking the time to let us know how we are doing. I'm very happy to hear that you have decided to go with M&M to get your doors done. We know you will not be disappointed, we have a great crew and know they will be effective, efficient and professional! Please come back and let us know how everything turned out!

Ken L.
09/2013
5.0
remodeling, doors
  + 0 more
We were very happy with this installation. The installers arrived on time and removed the existing doors in a timely manner. The installers inspected the openings and replaced all rotted wood prior to installing the new replacement doors. The new doors installation went well and all of the doors operate quietly and smoothly. All of the replacement trim looks great. One thing we liked was that the installers were M&M employees, not some subcontractors. We felt the installers had good experience and could handle any unforeseen circumstances. We will be using M&M Remodeling services in the future.
Description of Work: We had one entry door, with sidelights, installed and two patio doors installed.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro

Response from M&M Home Remodeling Services
Thank you for sharing your experience with other members. I'm very happy to hear that your experience was great! We really appreciate your feedback and the time you took to let us know how we did.

Kurt L.
09/2013
2.0
siding
  + -1 more
Wanted an estimate for re-siding my house. Scheduled an appointment, and the guy came out and met with me, took measurements, etc. and left. He said he'd have a bid for me in a couple days. I never heard another word from them. I went with another contractor.
Description of Work: Nothing.

Rating CategoryRating out of 5
professionalism
3.0
responsiveness
1.0
punctuality
4.0


Jeff B.
09/2013
1.0
roofing, gutter repair, siding, replacement windows
  + 2 more
This company is a tale of 2 personalities. The process started in May 2013. I needed full rehab on inside and outside of a 4-unit apartment building in the south burbs. Mark who quoted windows, gutters, soffit and fascia replacement on a 4-unit apartment building needing rehab is professional, knowledgeable, detailed, prompt and responsive. He provided me a competitive quote and I was ready to move ahead with a $20K project. From first meeting Mark, I had the detailed quote for the project in about a week. I was hoping to have one company perform all the work but M&M will not have one person handle outside work and inside work so I was passed off to another associate for interior remodel. The experience went south from there ultimately with my determination that we were not a good fit. After about 2 weeks attempting to get an appointment, the interior sales associate came out and spent 2 hours going over the property so I was at last hopeful. Weeks went by and calls were made to get a resulting quote on the work. This company has some very weird requirements on presenting quotes. Although the exterior quote was presented seamlessly by email in about a week, M&M refuses to provide a written quote on interior work. About a month later,we were finally able to schedule a meet to review the quote - so I thought. Instead I was subjected to an electronic presentation on a tablet. The presentation was centered on pictures of the staff and all their different offices located in the metro area. It was explained that M&M is a high tech company and doesn't provide a quote in written form. After about a 45 minute presentation on the virtues of M&M I was shown a 5-line excel spreadsheet with a total quote of $90,000. The associate asked how I felt about it. I explained that I still had no idea what they were going to do for $90,000. If I was buying a car I wouldn't have known if it was a Yugo or a Mercedes. I ended the presentation explaining that this was not a good fit. 2 weeks later I get a phone call from a very nice woman (don't recall her name) following up on my experience. I explained all the above. She apologized and wanted an opportunity to correct the error. I reluctantly agreed. Now enters Trevor - the manager of the interior division. He explained that the job had been quoted properly. I repeatedly asked to get a copy of the quote but he would not produce it. Once again Trevor assigns another sales associate and determines that they need to re-quote. Once again M&M refuses to present a quote in any other manner than in person. After many attempts to schedule a meeting, I have thrown in the towel on getting anything from them. If this company can't figure out how to deliver a professional quote in 3 months time I can only imagine how any project may advance. After my initial meeting with Mark I am so disappointed with the outcome of the interior division and having to write this review. The woman that followed up was also a class act. She earned them another opportunity but they bungled it again. M&M has some good talent. Unfortunately it is severely impeded by weaknesses in other parts of the organization. If you decide to give this company a try, be sure to get a detailed quote. Good luck with that!
Description of Work: Attempt at quoting a big job twice. Over a 3-month period this company was unable to produce a professional quote. The did absolutely nothing.

Rating CategoryRating out of 5
professionalism
1.0
responsiveness
1.0
punctuality
1.0

$120,000

John P.
08/2013
5.0
gutter repair, roofing
  + 0 more
I left for work early on the day they were to install my gutters, and when I came home, I had new gutters. The only problem was with the placement of one downspout. The workers had it draining into the gutter on my sunroom, but I wanted it to drain to the ground so that I can install a rain barrel. I spoke with Kathy (in the office) and Jeremy ( the salesman), who went over the drawings for the installation and was able to get the downspout fixed as I wanted it. In fact, I didn't realize the work had been done until this morning, when I spoke with George when he came out to see if I was happy with the work. There was a minor problem with some flashing from the roofing job that was done earlier and George went up to fix that. While he was on the roof, he noticed that the leaf guards installed in my gutters needed a few extra screws. He said he would have a crew swing past on their way back to the shop and take care of the problem. Overall, a very good job of installing the gutters and helping me with the minor problems I had. Thanks to everyone involved with the job.
Description of Work: M & M replaced the gutters on my house with seamless gutters.

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
4.0
punctuality
5.0

Yes, I recommend this pro
$2,370

Response from M&M Home Remodeling Services
Thank so much for taking the time out of your day to let us know how we did! Please let us know if there is anything else we can help you with!

John P.
08/2013
5.0
roofing
  + -1 more
I am very pleased with the work done on my roof replacement. I had a minor problem with the roofing over a bay window on my house. When I came home, it looked like they missed it. After a couple of phone calls to Kathy in the office and Jeremy, the salesman, I found that the problem with the bay window roof was on my end. From where i was looking and the way the light was hitting it, I couldn't tell that they had indeed replaced the shingles on the bay window. Minor problem was no problem at all.
Description of Work: I had M & M come out a few years ago for an estimate so that I would have an idea of what I would be paying. When I was finally ready to have the work done, the estimate was within 10% of the previous one. They did a total tear off of my old roof, so they could apply underlayment that was more protective than felt paper and installed extra roof vents, since my home had only a few. I was heading out of town the morning they came to do the work. I met the crew and gave them my cell number incase there were any questions or problems. I received a call to let me know they needed to replace some of the 1"x 8" boards. When I came home that evening, the only things that showed anyone worked on my house were the new roof and their sign in my front yard.

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
4.0
punctuality
5.0

Yes, I recommend this pro
$6,440

KAREN P.
08/2013
5.0
roofing
  + -1 more
It went very well. They were very clean and very professional. They hauled all the stuff around and I did not have to lose my driveway to a dumpster because they hauled it away in their truck. I was very appreciative of their services. They have given me a price on something else but I have not done that yet. We are looking into having our kitchen and bathroom remodeled but we have not been ready yet to tear up the inside of the house. We paid a little over $6,000 but we had three roofs and two layers of shingles. They had to remove everything and replace a couple of rotten boards and put a whole new roof on. They were reliable and they protected all my windows by putting boards across them when they were scraping all the stuff off the roof. In case anything came off the roof, they policed the yard very well. Everybody I have seen who was getting a roof in the area basically ended up with a dumpster taking up their driveway for a day or two but I did not so I did not lose places to work or park my car. They were not the most expensive but not the cheapest either. I have not been able to bid the price but I was familiar with their company being in business for a long time. I have seen their truck all around and basically seen the jobs they have done.
Description of Work: We used M&M Home Remodeling Services last December for replacing our roof and a couple of rotten boards in it.

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$6,000

Thomas D.
08/2013
5.0
roofing
  + -1 more
They were good. I will use them again in the future.
Description of Work: I used M&M Home Remodeling Services for doing my roof.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$4,500

Kathleen J. K.
08/2013
4.0
gutter repair, roofing
  + 0 more
They were too high. Their estimate was $9047. They were fine. The young man that came to do the estimate was new; so we did not get the actual estimate until almost a week after he was out here, but otherwise everything was fine.
Description of Work: We got an estimate from M&M Home Remodeling Services for new gutters, soffits and fascia.

Rating CategoryRating out of 5
professionalism
4.0
responsiveness
2.0
punctuality
4.0

Yes, I recommend this pro

Victoria F.
08/2013
5.0
roofing
  + -1 more
They were very prompt and good about giving me a quote. The quote was for was $10000. Their prices were higher than the other ones that we got but outside of that they were very professional gave us a lot of options and they seemed very knowledgeable. It was a very pleasant experience all around and we would definitely give them a chance. They came out when they said they would, they explained everything and he was very good.
Description of Work: I received an estimate from M&M Home Remodeling Services for roof top and fascia.

Rating CategoryRating out of 5
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$10,000

Patrick M.
08/2013
5.0
roofing
  + -1 more
I called for an estimate. Spiro from M&M arrived on time and gave me a detailed estimate. Their estimate was about the same as I received from another roofing company. I choose M&M based on their professionalism and their Angies list reviews. I called their insurance agent to confirm their liability coverage. I signed the contract and paid one third down. M&M emailed me when they ordered the roofing materials, when the materials arrived, and when the crew was scheduled to arrive at my home. They started on a Friday and finished on the next Monday. The crew secured the roof so it DID NOT leak over the weekend even though we had a heavy rain. Jose Lara was the on site Project Manager and kept me well informed throughout the process. They left the outside area cleaner than when they arrived. A Manager from M&M came out to inspect the work and to make sure that I was satisfied with my new roof. Overall, this was a stress free event for me. I would have rather spent the $4600 to go on vacation, but it is nice to know I don't have to worry about a leaky roof.
Description of Work: Installed new roof section, vents, and fan.

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$4,600

Ed W.
07/2013
5.0
roofing
  + -1 more
The service provided by M&M Home Remodeling Services turned out fantastic.
Description of Work: They installed a new roof on my home.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$11,000

Gregory G.
07/2013
5.0
roofing, skylights
  + 0 more
No less than half a dozen windows, doors, or roofing contracts thru this company, and I will not hesitate to use their newly established home remodeling services division as needed (ie deck, kitchen).
Description of Work: I called to purchase new skylights, never hesitating to call M&M first, usually only provider used! MM determined trying repair only after inspection, no new skylights needed, no leaks 14 months. Honest opinions at MM.

Rating CategoryRating out of 5
quality
5.0
value
4.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$70

c steven R.
06/2013
5.0
roofing
  + -1 more
excellent. completed on time on budget as per contract cleaned area efficient will use them again; highly recommend them.
Description of Work: patched roof; reinstalled and leveled gutter.

Rating CategoryRating out of 5
quality
5.0
value
5.0
professionalism
5.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro
$525

Pam H.
06/2013
1.0
roofing
  + -1 more
Not only was their price more than $1000 higher than the contractor we chose, but there was no follow-up from Jim to discuss their proposal and see if we had made a decision. ?We did get a call from a girl in the office and I told her we would like another price, this time not on their top of the line product. ?She said she would get the request to Jim, who never called us back! ?About 10 more days passed and I got another call from the office, at which time I told her that Jim never contacted us, we chose a competitor, and our roof was already DONE! After a couple of emails back and forth, the sales manager called, apologizing for lack of follow-up on Jim's part. ?He asked if we needed any other work done, and I asked if they install whole house fans. ?He replied they do and he would have someone contact me. ?2 more days passed before I got a call from a different sales associate, who took the information over the phone. At no time did he come out to see our ceiling, take measurements, or just to meet us. ?Rather, I was told that they could not find a fan to fit the opening in our ceiling! ?How is it that other electricians had no problems finding a 24" fan!?! I believe they did not want to be bothered with this relatively small job, so they passed. Do yourself a favor....don't bother calling M&M if you need ANY work done. ?They obviously don't need you!
Description of Work: Sales associate Jim came out and measured our house then returned with a proposal in his iPad. That part was pretty nice, since I love technology. We did not hire them for many reasons.

Rating CategoryRating out of 5
value
1.0
professionalism
1.0
responsiveness
1.0

$8,250

not A.
05/2013
4.0
roofing
  + -1 more
The guy at M&M Home Remodeling Services was thorough and he gave me two options which they're happy to go by doing it. They gave me an estimate on each one. He was also on time.
Description of Work: M&M Home Remodeling Services just checked my roof and give me an estimate.

Rating CategoryRating out of 5
professionalism
4.0
responsiveness
5.0
punctuality
5.0

Yes, I recommend this pro


Service hours

Sunday:
8:00 AM - 4:00 PM
Monday:
7:00 AM - 7:00 PM
Tuesday:
7:00 AM - 7:00 PM
Wednesday:
7:00 AM - 7:00 PM
Thursday:
7:00 AM - 7:00 PM
Friday:
7:00 AM - 7:00 PM
Saturday:
7:00 AM - 6:00 PM

Licensing

Bonded

Insured

Licensed*

Trade License Locale
Indiana, Illinois
State Contractor License Requirements

All statements concerning insurance, licenses, and bonds are informational only, and are self-reported. Since insurance, licenses and bonds can expire and can be cancelled, homeowners should always check such information for themselves. To find more licensing information for your state, visit our State Contractor License Requirements page.

*Contact business to see additional licenses.


Service Categories

Roofing,
Gutters,
Siding,
Windows,
Skylights

FAQ

M&M Home Remodeling Services is currently rated 4.5 overall out of 5.

Sunday: 8:00 AM - 4:00 PM

Monday: 7:00 AM - 7:00 PM

Tuesday: 7:00 AM - 7:00 PM

Wednesday: 7:00 AM - 7:00 PM

Thursday: 7:00 AM - 7:00 PM

Friday: 7:00 AM - 7:00 PM

Saturday: 7:00 AM - 6:00 PM

M&M Home Remodeling Services accepts the following forms of payment: American Express,Check,Discover,Financing Available,MasterCard,Visa
Yes, M&M Home Remodeling Services offers free project estimates.
No, M&M Home Remodeling Services does not offer eco-friendly accreditations.
Yes, M&M Home Remodeling Services offers a 5% senior discount.
No, M&M Home Remodeling Services does not offer emergency services.
Yes, M&M Home Remodeling Services offers warranties.
M&M Home Remodeling Services offers the following services: Roofing, Windows, Entry Doors, Siding, Soffit, Fascia, Gutters

Service hours

Sunday:
8:00 AM - 4:00 PM
Monday:
7:00 AM - 7:00 PM
Tuesday:
7:00 AM - 7:00 PM
Wednesday:
7:00 AM - 7:00 PM
Thursday:
7:00 AM - 7:00 PM
Friday:
7:00 AM - 7:00 PM
Saturday:
7:00 AM - 6:00 PM