I know how you feel. i got tons of the tiny black monsters (did you know they can bite/sting if they crawl on ya?) and nothing i can do short of squashing any one i see will work. ant baits, work for a good two days, then they're back. no food left out, no problems with food in storage, but they come anyways.
They're attracted to ANYTHING. even water, humidity. RVs that are humid or in humid areas are great targets for those 'piss ants' sorry for language but that's the name for them. they literally stink like heck when squashed, and sadly that's the smell of their pheromones, so any ant squashed sends out rescue teams of more ants. there's no nest or central queen, just millions of fast-breeding workers. and they come from outside, not in, so finding the source is almost second to impossible. you will never find out where they're coming from, just keep playing whack a mole with whatever you got on hand. and make sure to keep the sinks dry, and NEVER leave food out. even grease from the oven is a great attractant. soda cans, even bread. you will never get rid of them all, but you can greatly reduce them to almost the point you won't see more than one or two. i just try to keep them out of my bed. never eat around beds, lest you like ants in your pants.
IF your RV or Travel Trailer leaks, you may not see it, esp if it's not a visible one, but one that comes and collects inside the framework but never shows up. those moisture traps are big havens for those piss ants. they really love moisture. and if there's a water leak, even a hidden one or tiny one, they're there. ants harbor it.
We have never had a major problem "KNOCK ON WOOD". We have had a few but I have start putting some Seven Dust around all the jacks, tires, and cords and we haven't had any since.
2000 Thor Cub F21
Nights camped in 2008: 10
Nights camped in 2009: 20
Goal for nights camped in 2009: 20+
I second the TERRO product perviously mentioned. Living in South Fla. we had a major ant problem in our house. I sprayed, bought traps etc and the ants always returned in full force. A friend told about the Terro product. I bought a couple of boxes at Lowes for inside and outside of our hosue....and within a day or so the ants were gone. That was about 2-3 months ago and I havent seen an ant yet.
Terro works great. They sell nice little trays with openings only the ants fit through. Ants eat it, take it back to the nest, no more ants. I have had this eliminate ants in one day. Spraying is fine but it doesn't kill the source. Be careful with inside pets. If they eat the ants that have eaten the Terro, could be bad.
A friend told me diatomaceous earth, the stuff you use for pool filters is suppossed to work. You spread it all around and under the outside of camper. I guess ants don't like to walk on it. Been using that, so far so good. Also I guess its pretty environmentaly safe, just ground up sea shells or something, I believe.
Best solution that i found besides avoiding any food or garbage inside the home (don't use a trash bin inside, you'll have ants in a heartbeat!) is spraying PAM cooking oil spray on the water hose, electrical cords, and the tires. the ants will avoid it because they literally get 'stuck' and won't be able to move. it's natural and more safe than pesticides plus you probably keep some for the frying pan so there ya go.