Some dealers asses a hefty surcharge per gallon. While some dealers provide a free airport pick up, others charge for this service. Ask them what their charge is since it may be cheaper to take a taxi. Many independents don't provide one way rentals. Cruise America and American Safari offer one way drop offs for a fee between many rental locations by request.
Some dealers provide livability packages.
These are divided into personal kits such as linens and eating utensils and vehicle kits containing pots and pans and cooking utensils. Save on these fees. Bring from home what you need, buy at a local discount store, or borrow from friends and family if you're visiting them. To save money, comparison shop. Consider renting an RV in the off season.