I hope somebody has a good idea for you because I'm not going to be very much help. Mrs. Grouch and I worked through this issue backward.

I had pretty much discarded the idea of owning a trike due to the transportation issue. Then, at the Rans recumbent rally, a dealer from colorado showed me a folding ICE trike. I was impressed. After returning home, we drove my wife's Saturn to a local dealer and said: "If you can show her how she can fit the trike into her car and assemble it so she can ride, we'll buy it." It took awhile but the owner figured out how to do it and we drove home with a Greenspeed GT3 in the trunk. The Greenspeed cost a bit more than she wanted to spend but we didn't have to buy a rack and receiver.