Comment by jrockway

I don't think there's a good one-size-fits-all rule. A 3 bedroom unit could be 3 couples living together and splitting the rent, or it could be 1 family, or it could just be 1 person who wants an office and a gym. The rule should probably be "1 space for car owned", like when you go to buy a car, you have to prove that you have a place to park it.