One new building proposal I have heard of has cut the number of car parks and instead allowed for two care share spaces specifically for residents. That’s your answer. If you can generate the interest in a car share service just for your residents, I’m sure they will put a car in your building, then you don’t have to worry about allocating use, servicing or insuring the vehicle.
Have a look at the websites for Hertz247, DriveMyCar and GoGet and perhaps they have the answer you are looking for.