Basement Studio Apartment?

[Ryan Cormier]

I am buying a 3 unit house with a basement (4th unit) that was built but not permitted. I am new to bigger pockets and real estate and am hoping someone may be able to give me a bulletpoint step list of how to go about getting this studio apartment legal. The house is in Massachusetts.

Basement has bath with sink, shower, toilet. It has kitchen with range and fridge. It has gas hook up in living room for a gas parlor heater. 

Any advice would be great appreciated. 

P.s. !st and 2nd floor may have knob and tube, does it make sense to pull down walls and redo or have electrician just poke holes patch and paint?

[Johann Jells]

DO NOT go to Buildings before you talk to a zoning bar lawyer! Or at least a local architect. Odd are there's a good reason it's not permitted. Likely density code, but it does need 2nd egress, windows and be 50% above ground to be legal around here. There's a lot of this in my city: "bonus apartments".  There's rules to teh cat and mouse game like pulling out the range if there's an inspection, so it's not "officially" a kitchen. As long as it's safe and up to code the biggest drawback is you can't claim the income when getting a loan.