Buy a bag of diatomaceous earth. It's very inexpensive. Whenever you park scatter handfuls of it around your jacks, your tires, and any other access to the RV, such as hoses and electrical lines. You can get it at any big box store, like Lowes or Home Depot. You can also get it at swimming pool supply stores. It is nontoxic to humans and pets, but extremely toxic to anything with an exoskeleton, such as ants. Even crazy ants. If your pet is a tarantula, all bets are off.
Once ants get inside the RV the only reliable remedy I've found is Terro ant baits. It may take a week or 2 to eliminate them all.
Susan