Hey guys, please accept my meager apologies for non-contribution, but I'm all tied up with my own battle with the VA. (Shameless plug to support your local disabled Vet !) But to piggyback onto what formysweetie suBathmateitted I'd like to remind you about pouring too much time, money and effort into a place if you don't have permits. Up there in "Taxachusetts" them damn code inspectors can be pretty fukkin' ruthless as they make you rip out all the work you've done as well as summon yer poor dumb ass to court and impose heavy fines.
I live in Virginia and I'm pretty familiar with our codes, yours will be very similar and if you want to minimize any potential trouble you may want to reference your "UNIFORM STATEWIDE BUILDING CODE" and then your local codes which derive from the State Code. Usually you have to have permits for health, (plumbing, HVAC), safety, (electrical), structural integrity, (walls, floors, ceilings) or if you're breaking the weather tight integrity of the house, (doors, windows, rooves) and, basically, whatever else your local govornment says you do. As a guy who's had his own fair share with "Code Enforcement" (Virginia Beach is absolutely FASCIST when it comes to permits) I'd hate to see you guys pour heart and soul into Mike's house and have to rip out and replace. Hope my random ramblings were at least helpful. Good Luck !