It’s way more expensive to hire from an airport location than a town location.
Your hire will start when you collect the car, and your paperwork will show a date and time for when the car is due to be returned.
If you’re going to be late, ring them and you may get an hour or two grace period.
If you don’t ring them and are late, you’ll be paying for another days hire.
Always, always walk round the vehicle and note down any damage.
You should get some sort of notification of what damage is on the vehicle already, but mark everything and take a photo of each panel and the wheels.
If the car has a full tank, you’ll often get the option to purchase that tank of fuel, so there’s no need to return it full of fuel.
However, if you’re not doing many miles, it’s easier just to refuel prior to returning the car.
If you are doing loads of miles, and you purchase the tank of fuel, you’ll want to return the car with the petrol light flashing, because whatever fuel you leave in the car, is fuel you have paid for.