1) could ask the local dealer, as a courtesy, no charge, to keep an index box with owners and their colors, who may want to swap. (no shipping charges). ... after contact, swap in a mid point parking lot, or at ones home. hour or two, to switch.
2) set up a thread or section here, for people who want to switch, in same cities.
3) start a local web club, for switching panels, wheels, etc,.
4) local paper ad in your city.
smart could offer a collectors special edition panel color run, of maybe 1000 panels, every six months or so.
candy apple red, gun metal silver gray, champaign metallic, would be good se's.
like getting a unique special edition all new smart, every six months or so.