Prior to your drop-off day, be sure to find out from the rental agency at what time they expect you to return your cheap rental vehicle. Always ensure that you have enough time to return the car so that it does not arrive late or there may be late fees.
In some cases, you can return the rental vehicle to a different city or even state from where you picked it up. Make sure to check the policy regarding returns with the rental agency beforehand. Returning your cheap rental car to another location might be a convenience to you but it could incur an extra fee.
Some companies even offer a "drive-away" program. During certain seasons or periods, some car rental companies require vehicles to be transported to different locations. If driving one way suits your situation, then it might be in your best interest to inquire about any such programs.
Some agencies have free customer drop-off to the airports. This is something you can inquire about when picking up the vehicle. Check to see the distance of the drop-off or how many minutes it will likely take to get there.
Some car rental companies will offer an Express Drop-off Service. Sometimes at an extra cost, you can drop-off the cheap rental car, the keys and the contract without having to physically meet with a counter agent. This is handy if you're in a rush to get to the airport.