The bad thing is if you want to sell one Tank Car you don´t get nothing CRs.There are many cars (Capuccino RM for example) which you "sell" without win CRs.That means,delete the car,but try to sell it.Maybe you win some CRs or not
If appaears the text "You can´t sell this car.Do you want delete it?" you don´t win nothing,but if appears CRs,I think is better sell or tuned for Online Races