Every marketing list will have conditions relating to it’s use, controlled by the list owner.
Rental (single use) is a strict one time use only.
Rental (multi use) means you can use the list as many times as permitted within the rental period.
Purchasing means you may use the list as many times as you like, and for any period of time you require. The cost for purchasing can often be higher than rental, and it is also your responsibility to maintain the list to ensure it remains accurate and compliant.