Plumber Recommendations for Heater Replacements in Boston, MA

[Dan Borecki]

Does anybody have a recommendation(s) of licensed plumbers in the Boston, MA area?  I have a 3 family apartment building built in 1900 and am looking to replace 1, maybe 2 (depending on price) hot water boiler heating systems, as well as a gas space heater. Each of the current heating units are around 30-40 years old and fully depreciated. 

As some background, I just had a MassSave home energy audit and 1 of the hot water heaters and the gas space heater came back with above code readings of CO emissions, so I need to replace those before I can proceed with the MassSave insulation work. 

The Mass Save program is willing to give up to a $50K interest free loan for 7 years to do all of the work and replace the heaters.  The usual loan cap is $25K, but they give up to a $50K loan for 2-4 unit properties. This is the reason for why I am considering replacing the 2nd hot water boilder depending on the price. 

Thank you!