Tradein is a tool to help consumers make informed new auto purchase decisions when trading in a vehicle. New vehicle purchase tax is calculated by the new auto price which is the price after dealer rebates plus manufacturer incentives and aftermarket dealer add-ons minus the down payment and trade value. Adding tax title license and gap insurance will give the net price. Adding your trade in payoff amount will give you the total loan amount needed to make the new purchase. The total loan amount interest rate and term length will give you the monthly payments and total interest payed over the life of the loan. This tool helps consumers by eliminating confusion when dealers throw numbers at you and has been field tested at various dealerships. This app will put you in the drivers seat when negotiating new auto tradein deals. Be smart spend a few bucks on this app and potentially save thousands by walking out on bad deals.