Hello- I agree with below. You are spinning your wheels until you speak with the town's building inspector, and also someone from the Zoning Department, if needed.
I assume you have public sewer service? That makes it a bit easier.
what about parking offstreet for an additional tenant? That could be a problem.
Once you find that stuff out, let me know if you need additional help. I know a few good local RE attorneys that could make it easy, and they are reasonable. Thanks and good luck,
Ken L.... more