This summer is expected to be chaotic when it comes to booking a campsite. According to the RV Industry Association, more than 11.2 million American households own an RV. That’s an increase of more than 25% from 10 years ago, and more than 60% from 20 years ago. And as many new RV owners are itching to use their RVs to travel, some RV parks say they are already booked. “It seems to be the busiest year that we’ve seen so far, especially with people needing to stay month to…