Before talking about test drive, something first. Keep RP-locked cars available to view in dealer at least.
You get into any dealer, pick any car, a button there to test drive it. Stock car, no extras. Maybe drop player into a private racetrack to get the feel of it. RP-locked car should be accessible to test drives too, just you can't buy it until you got it unlocked using RP.
EDIT: Unique cars too.
You get into any dealer, pick any car, a button there to test drive it. Stock car, no extras. Maybe drop player into a private racetrack to get the feel of it. RP-locked car should be accessible to test drives too, just you can't buy it until you got it unlocked using RP.
EDIT: Unique cars too.