Trade-ins are one way, advantage to the dealer. The trade value is not the retail resell value, trade-ins can be 60% to 75% of full retail. Remember Business 101, “Buy low then sell high!” So the car is worth is $3000 minus the $1000 not $5000 minus $1000. That is $2000 for the dealer to fix, repair, cover warranty expenses (returns for quality issues) and finally profit.