Go with cheap die-cast cars like the ones available at small drug stores etc. They have great detail and can be dis-assembled, modded, then re-assembled. If you wanna look on amazon then maisto is the thing to look for. I have several now.
If you find some at a live physical location, put a mini in your pocket and hold it up to the car to check scale, as some of them are too big or too small. The mini trick always works. If you wanna go get nearly-fully-painted aquarium terrain to use on your game table, the mini trick works there too.