The specific numbers to request before signing anything.
Ask for the money factor directly. It's legally disclosed in the contract under Regulation M, but many dealers won't volunteer it verbally — ask by name before you're at the signing table.
Get the residual value and percentage. Compare it against independent guides where available; a residual that looks unusually low inflates your monthly payment.
Get the total-of-payments figure from the disclosure box, and request it for both a with-down and zero-down version of the same offer.
Confirm the mileage allowance against your actual annual driving — excess mileage charges are billed per mile at turn-in and add up fast if the allowance is set too low.
Ask whether gap coverage is included or needs to be purchased separately.
Get the disposition and acquisition fee amounts in writing — both are standard and negotiable more often than dealers imply.