I know nothing about the RV park business, but I do know, in my business and in many other businesses, competing on price is a really bad idea. It is best in my opinion to compete on service and quality. Competing on price, in my experience tends to attract , really cheap people. Who most business owners will tell you, are very often the most difficult to deal with. And the only people they will send to you tend to be really cheap people as well.
So end of the day, I feel it is best to set your prices high enough, so you don't attract those folks in the first place. Has worked for me at least