Basement Occupancy when Buying New Property

[Rob Wii]

Hi,

I am looking at purchasing a detached one family property in Queens with a fully finished basement. It is advertised as one living level. 

The property is classed as A9-1 Family Dwelling in zoning distric R4-1 and Basement Type 2 (not sure what this means).

Currently the basement space is being used as a recreational area, laundry and has a washroom. It's only means of access is from the first floor stair. The ceiling is 7 feet high, has two small side windows onto the walkway and one window onto the rear yard. 

My question is how do I know if this area would be able to be used as an occupied basement if alterations and access points were added (egress stoop through front or rear). I am not sure if exactly half of the basement is above grade as the property is on a slope. 

Currently there is one bedroom on the first floor but this would not be enough when considering purchasing the propoerty. The plan would be to add more however there is not enough room on the 1st floor.

Any suggestions on info would be greatly appreciated. 

*Added in wrong area, sorry.