We use a product called MouseFree.
http://www.mouse-free.com/ We spray it on any the points of contact that rodents or crawling insects would use, like the 6 point leveling jack pads, cables, hoses, etc., and also on parts of the mainframe and axles. It doesn't cause rusting and cleans easily. It has a slight menthol odor and thus the deterrent. Since using it, we've not had any ants or rodent issues and we travel all over, including FL. It's available online and at certain dealerships. It's pricey, but if you buy two gallons of it, you can get a dedicated air sprayer with it at no extra cost. I use a small 3 gallon air compressor. Because it is a gelatinous product, it does attract dirt from the highway, but when we store our 5th, I use a power washer and it cleans up easily. I bought the two gallons with sprayer and use it a little more sparingly than what the company advocates and at the end of three years, I still have about a half gallon left. It's safe and easy to use.