flat floor in cars

Could you design a car with a flat floor like a van? I have to use a step stool to get into my Windstar because I am handicapped. I can't get in a car because of the raised frame at the door. In the van I can just slide my feet over. Also, need adjustable seats on both sides of car and enough head room to make the seat high like sitting in a chair instead of having the legs scrunched up. I'm sure many handicapped and older people would appreciate a car like that.