Possibility of adding 2 units in basement of raised foundation

[Rich Somers]

I'm in currently in contract on a 5 unit multi family and my inspection is scheduled for next week.  I'm going to walk a few contractors through to bid the rehab (mostly cosmetic stuff for the existing units).  One of the things I also want to do is clean out the basement, run plumbing and electrical to it in order to utilize some coin operated laundry.  The building is 100 + years old, and has a raised foundation...I'm sure there is moisture down there.  Question is this:  Since I'm already running plumbing and electrical down there, what are the odds I can legally and safely add a couple livable units down there?  What kinds of things would I need to know prior to determining this?  

Thanks guys, I look forward to hearing your responses!