How dealers value trade-ins
Most franchised dealers use Black Book (wholesale auction prices) — not KBB consumer value. They subtract reconditioning estimates and a profit margin. Result: typical trade-in offers come in 15-25% below private-party KBB. Specialty cars and high-demand SUVs sometimes get above-Black-Book offers when the dealer needs inventory.
Get three quotes in writing
Get a written trade-in number from: (1) the dealer you are buying from, (2) CarMax (free, valid 7 days), and (3) Carvana or Vroom (instant online). Bring the strongest two with you. Dealers will often match CarMax to keep the deal in-house.
Sales tax savings (most states)
In 42 states, sales tax is calculated on the difference between the new car price and the trade-in value. On a $40K new car with a $15K trade in a 7% sales-tax state, trading in saves $1,050. Always include this in trade-vs-private-sale math — it often closes the gap.
What to do before the appraisal
Wash and vacuum. Remove personal items. Fix obvious cosmetic items under $200 (a $100 dent removal can add $500 to the offer). Skip expensive repairs — you will not recover them. Bring all keys, the owner's manual, and service records (especially recent timing belt, transmission service, tires).
Negotiate trade and purchase separately
Walk in saying you want the out-the-door price on the new car, then discuss the trade after. Dealers love the 'four-square' worksheet because it lets them shuffle dollars between trade, price, financing, and down payment — confusing all four numbers. Demand each number stand alone.