Compact Cars as a rental are a better deal.
Unless you are traveling with a large number of people or have lots of luggage, reserve a cheaper compact car.
The compact car is also fuel-efficient and easier to park.
According to AARP Bulletin Compacts are not popular and rental companies fill their lots with bigger cars: If they run out of compacts you may get a free upgrade.
Fuel consumption will me more expensive but you will have the luxury of more space for less.