1. Water Pressure Regulator: The pressure of many RV parks’ fresh water systems is too high and may blow out your RV water pipes in a hurry. This is a MUST say the experts.
2. Ten foot, 25 foot and 50 foot hoses: Three sizes are handy and you’ll always have a back-up if one leaks or bursts.
3. Dog bone electrical adapter from 30 to 15 amps: Many older campgrounds still use the home-type 3-prong 110 plug.
4. Sewer hose plug/adapter: This seals the end of the sewer hose into the RV park’s sewer hole and is required by some parks. It keeps the system free of flies/odors.
5. Voltage meter/polarity gauge: This lets you know how much juice is flowing from the RV park’s electrical system and if the polarity is correct.
6. Five or 10-gallon container for water: Always good to have an extra container of fresh water, just in case.
7. Cupholder for the driver and co-pilot: Not that many new RV’s have them, believe it or not!
8. Back-flusher for the black water sewer line: Quick way to flush out the black water tank whend dumping it.
9. Heavy duty 50’ and 100’ extension cord: You never know when you’ll be a long way to a power connection, especially in overflow RV camping areas.
10. Surge protector: If you use a computer or other electronic device, you’ll want to protect them from the notorious surges found in RV parks.

These and several other extras are available on most of today’s recreational vehicles. Perusing RV web sites will give you a good idea of what’s available and the cost of each item.