Canner Law & Associates, P.C.

Residential Real Estate Law • Buyer Representation • Seller Representation • Condominium Law • Landlord/Tenant Law

“Joe helped my wife and I with the closing on our condo in Cambridge. We found him to be professional and very personable. He walked us through the mire of closing paperwork step by step and took the time to make sure we understood everything to our satisfaction. He was punctual with all appointments and correspondence and made the whole experience very easy. I would highly recommend him to help anyone with the closing of their home.” – Seller

Attorney Joe O’Sullivan has been with Canner Law & Associates since 2015. Prior to that time he operated his own firm, O’Sullivan Law, P.C., based in North Reading, MA. He focuses on real estate conveyancing and land title matters including all aspects of purchases, sales and refinances, including purchase and sale negotiation, condominium document review, condominium conversions and residential leases.

Joe graduated from New England Law | Boston in 2012 after earning his B.S. from St. Thomas Aquinas College in Sparkill, NY in 2004. While at New England Law | Boston, he founded and served as the President of the American-Irish Law Society and took on other leadership roles, including with the Boston Bar Association Pro Bono Committee.

Memberships and Affiliations:

Massachusetts Real Estate Bar Association

Massachusetts Bar Association

Boston Bar Association.

The Greater Boston Association of Realtors (GBAR)

National Association of Hispanic Real Estate Professionals (NAHREP)

Boston Irish Business Association (BIBA)

Business Network International (BNI)

Family and interests:

Joe was born in Limerick, Ireland, raised in Orangeburg, NY, and has lived in the greater Boston area since 2008. Joe currently lives in Waltham, MA. He is an avid sports fan, enjoys live music and trying new restaurants.”

Jonathan, you were an absolute pleasure to work with and we will absolutely be using you again when we buy our next property in Massachusetts

-Bob S.

My wife passed away last year and Jonathan helped me get everything in order to help sell our home. It is difficult for me to get around, so he came over several times to meet with me in person to sign documents and talk hockey. He is a wonderful young man. I am very happy with his services. -Jim C.

I am in the military and relocate every few years for my job.  As a result, my wife and I have owned houses in five different states before moving to Massachusetts.  We had been through the home buying process before and it had been very stressful.  However, working with Jon was such a different experience for us.  He is really knowledgeable and good at communicating.  He did a great job of explaining the process to us in a very easy to understand way – and he was funny too.  The entire process was very enjoyable.  We wish he could practice in more states.

-Zach L.

I cannot say enough good things about Jonathan.  I was referred to him by a mutual friend to help me with the sale of our house.  My husband and I had lived there for 25 years and had raised our children there, so it was a very emotional process for us.  Jonathan was so kind and understanding throughout.  It felt like we were dealing with an old friend, which is why we invited him over for beers afterwards!  He is a great attorney and an even better person.

-Mary F.

My wife and I are so thankful we chose Canner Law and Jonathan as our attorney to help us buy our home.  The day before our closing was set to take place, the people selling their home to us received what they thought was a better offer than ours.  When we showed up to the closing, the sellers and their attorney indicated that they were not going to sell to us.  We were devastated.  We had just sold our home a couple days prior and we were living in a hotel with our kids for the time being.  The school year was starting in a few weeks and we were so concerned.

Jonathan immediately knew the legal consequences of the sellers actions and began negotiating with their attorney.  He was very calm, intelligent and direct with the sellers attorney, who became flustered.  Let’s just say that we were glad that Jonathan was representing us!!

The negotiation process went on for over three hours.  Jonathan continually took us into the hall to explain everything that was going on. He even called his office and had his colleagues start drafting a lawsuit in case the closing didn’t happen.  It was really reassuring to know we were in such capable hands.

Eventually the sellers decided to sell the home to us and avoid any lawsuits.  We closed that day and officially became owners of the home that afternoon.

We truly cannot thank Jonathan enough and highly recommend him to anyone looking for a real estate attorney.

-Matt H.

Expertise reviewed 159 real estate law firms in Boston, and picked the Top 19. The criteria for selection included: reputation, credibility, experience, availability, professionalism and engagement. We are honored to be recognized. Thank you to my entire team, our terrific vendors, title insurance partners, and of course, the talented and dedicated realtors and mortgage originators we work with who helped Canner Law make the list of top real estate law firms in Boston!

Thank you Alex!

Thank you Alex! See review here!

Our family had a long-distance, unexpected estate sale in Massachusetts. The process had the potential to be messy given the probate situation. However Marc and his associates were all incredibly responsive, helpful and professional in representing us on all sale needs and helping us through this difficult process which went smoothly and successfully as a result. I would highly recommend Canner Law. I was very impressed and very grateful for both their professionalism and also their personal touch in guiding us through.

Sarah B. Plainfield, NJ

Buyer, November 2017

$350K Townhouse Buyer (Closed) Nov 29, 2017

Watertown, MA [Watertown Town]

Marc and his team were extremely helpful and made the confusing law process easy to understand. He and his team made sure I understood each step. They were easy to keep in contact with and answered any questions that came up.

Buyer, November 2017

$790K Multi-Family (2-4 Unit) Buyer (Closed) Nov 17, 2017

Melrose, MA [Melrose]

Super responsive and on top of his game!

Buyer, November 2017

Marc Canner and his team put clients first and are committed to problem solving to ensure the real estate deal comes through.

My wife and I were relocating from Connecticut to Massachusetts and Marc immediately set clear expectations for the home buying process in our new state. He worked through the Purchase & Sale Agreement to ensure all our conditions were met and caught a number of issues in the document submitted by the seller’s attorney. His team also provided an above and beyond level of service for our closing. Our lender had an issue with the Master Insurance coverage for our condo and Marc worked to first convince the Homeowners Association (HOA) that they needed the coverage the lender was asking for and then to help the HOA buy a new Master Insurance Policy that fit the lender’s criteria.

Despite stubbornness among parties involved, the deal closed and Marc and his team were instrumental in pushing it through. Throughout the process they were quick to respond to both phone calls and e-mails. A big THANK YOU to Marc and his team, which is very highly recommended.

Buyer, November 2017

I had the pleasure of working with Marc and his firm twice this summer - first with the purchase of our house and then with the sale of my condo. Marc has such a patient, calm demeanor which put me completely at ease during a very intense and often stressful process. Marc is professional, knowledgeable, thorough and available - essentially everything you want in a real estate attorney. I highly recommend him and the entire team.

Christine F.

Canner Law represented me during a recent condo purchase in Arlington, MA. I found Canner Law to be extremely responsive, detail oriented, and thorough. I would recommend Canner Law to anyone in the Greater Boston area.

Buyer, October, 2017

Hi Marc,

As you may know this is the second refinance we did with [redacted] and both closed at your offices and we had a great experience both times.

Both my wife and I appreciate the professionalism your team puts forth and if we ever see our home value come close to the buy price we will be selling and downsizing and will absolutely retain your services.

Thank you again and have a great day.

John C.

My husband and I have had the pleasure of working with Marc Canner both as first-time home buyers 6 years ago, and again with our second home purchase in 2012 and we would highly recommend him and his firm. He made the often complex process smooth and straightforward, and ensured we were on the right track every step of the way. We found him to be very responsive and always took the time to explain any questions we had.

Christel, Buyer

Marc is a detail-oriented, professional and punctual attorney. I have nothing but praise for his work ethic and have recommend him to my close friends and family members.

Jacque F., Buyer

Marc has expertly guided me through the closing process in a calm and expert manner.

Sue P., Buyer


I have worked with many attorneys over the years. There are not many that make themselves as available to their clients as you do. I appreciate that “Crunch Time” support you have given me over the years. Clients really appreciate your protection of their interest and your ability to explain complex legal details on a level at which they understand.

Mike M., Realtor

My wife and I just bought our first house about 9 months ago, and I was hesitant to refinance despite lower interest rates because of the hassle and generally negative experience we had the first time around. However, I am happy to report that things were a lot smoother this time around with the lender and the team at Canner Law, especially Kelly Bruce. Kelly was on top of everything and made sure things got done by the appropriate deadlines so we would not lose our "rate lock," which was no easy task considering that she had to clean up some items that hadn't been taken care of in connection with our initial home purchase.

Alex K, Borrower


Just a note to thank you again for your services. My parents and myself appreciated the quality of you work in both reviewing the P & S/condo docs for us and in conducting the actual Settlement. Everything went so very smoothly and on schedule and my parents–who [unlike myself] are veterans of many real estate transactions–were very satisfied.

As I said, I particularly valued your Real Estate Law Blog and its comprehensive and in-depth coverage of so many pertinent issues. It’s been an important resource for me in becoming better informed about real estate transactions, procedures, etc…in this last purchase but prior to it as well. I will not hesitate, going forward, to refer associates/friends/family to your services/practice.

Carlos R., Buyer