Leasing a car makes it possible for a senior to give back his or her car when they are no longer able to operate a vehicle. If a retiree's plans include a lot of long-distance motor vehicle travel, it may be more affordable to purchase a car, rather than lease one.
https://www.investopedia.com/articles/retirement/060916/should-retirees-buy-or-lease-cars.asp
Purchase Agreement Cancellation Letter Writing Tips Begin the letter by stating that you wish to cancel the purchase agreement with the receiver. Mention the reason behind this action. Mention the details regarding the compensation according to the agreement. Attach all the necessary documents along with the letter to make the process easy. Ensure correct usage of grammar.
https://www.letters.org/cancellation-letter/purchase-agreement-cancellation-letter.html
You have the right to cancel a contract to purchase a car from a motor car trader: unless you have accept delivery of the car within this time. [i] Three ‘clear days’ does not include the day on which the contract was signed, Saturday, Sunday or a public holiday. [ii] A notice setting-out your cooling-off rights must be included in the contract.
https://www.thecarexpert.co.uk/bought-a-car-and-changed-my-mind/
The vast majority of car dealers have no written policies that allow you to rescind the purchase agreement you've signed. This means your only recourse is to plead your case.
https://www.edmunds.com/car-buying/unwinding-the-deal-what-are-your-rights.html
doc for "car purchase contract between individuals".(Page 1 of about 16 results)