Duplex apt w/ basement- legal?

I am looking at a duplex apartment with the living/dining area in the first fl and the bedroom in the basement (no windows). Is this legal since, though not ideal, I could just as easily have the bedroom on the ground fl however from what I can decipher fr the housing code, any basement w/o any windows that's intended for "living purposes" is illegal, be it as a bedroom/living area etc. The place is great but I know this sometimes comes up as an issue and the current tenant is breaking their lease as they've just bought their own place. Could a lack of ventilation qualify as a housing violation and should I therefore run as far away as possible? Thank you!