How long do I have to return a vehicle purchased in Arkansas?

Please provide additional information. Generally, unless your contract says you can, you can't just "return a car". Especially a new car, since there is so much depreciation that the car you return after a week is not worth "new car" prices.

Threre is no "return period" unless your contract specificly gave you one.

The only time frame for cancelling a contract that most people confuse is for items bought from sales people in your home, and normaly you have 3 days to cancell that contract. So unless a door to door car salesman came by and sold you a car, normally the sale is final once you sign the contract.

If there was some fraud on the part of the seller, then it may differ.