Okay,I've heard lot of complaints that people cars are stolen while they're trading it,so here is how you can avoid this problem!
1:-When you're trading/exchanging cars please make sure that you've disabled your /pgoto command.
2:-Please try to trade/exchange your vehicle in a safe and private place.
3:-If somehow someone stole your car,note your car ID by typing /dl,and then give it to any high level admin,So they can reset that and reserve it for you!
4:-It'd be better if you trade a car in-front of any admin,then there will be less chance of getting stolen.
Follow the above instructions to avoid car "Stolen" problem.
If you have any questions please comment below!