It is a curious question. Typical house around here probably has 7 to 10 doors I am guessing, and a couple of cars. Might come out pretty even around here, but then we have rural areas, ghettos, third world etc. Lot of different societies with different vehicle to house ratios. Also then there are stores, factories, schools, government offices, etc. But then a lot of cars in junkyards and on sales lots. Stockpiles of doors and wheels in warehouses. And then if we consider there are other wheels than just on our automobiles, such as bicycles, roller skates, lawn mowers, inside of various mechanical devices, toy cars, but they have doors (or pseudo doors, though some will open).
Ah, I am going to say far more wheels than doors.