Japan is the approximately the same size as California, but with three times as many people. Space is an issue in cities of Japan. In my neighborhood of Onoharanishi, which is one of the more expensive suburbs in Osaka where people have more space than the average Japanese dweller, space is still at a premium. This family solved the “we have two cars but only one parking spot” problem. Rotary parking systems are common in cities, especially the big parking garages downtown. They are so much more efficient use of space. I wanted to wait at this house until the owner wanted to drive the silver car to find out how it works. I think you would have to take out the bottom car and then lower the silver car.
Taxis here have automatic doors as you can see in this video. This is a good idea because it prevents people from having to open the door when carrying lots of bags or children. It also prevents damage to the door if clients slam the doors too hard. I also noticed it is only the left side door that opens automatically, which in Japan where people drive on the left side of the road, it is a safety measure. People cannot open the door into the street and must exit the taxi curbside.