there should be a gross amount they crredited you for the trade-in . that's what to used. the gross amount would then be reduced by any payoff but has no effect on tax basis if the new item
ecample
sale price new item $50000 - that's its tax basis
less trade in value $20000 that's the sale price of the old item (assume cost $30000 and depreciation $15000
add loan payoff $10000, no effect on anything
cash paid $40000
if you were making bookkeeping entries
new item debit $50000
loan payoff debit $10000
old item depreciation debit $15000
old item credit $30000
cash credit $40000
taxable gain credit $ 5000 (trade in value $20 - cost $30 + depreciation $15)
(
