If you buy a car that is financed through the dealership, the dealer CAN cancel the contract, but only if it notifies you within 10 days of the date on the purchase contract.This type of financing is sometimes called a âspot delivery.â It is based on the language of the purchase contract.f you buy a car that is financed through the dealership, the dealer CAN cancel the contract, but only if it notifies you within 10 days of the date on the purchase contract.