Obviously it can be done. People do it all the time. It will take some planning and there might be some parks that won't work, but if having your toys with you, and I am one of those people, it is worth and extra planning it takes. You also don't have to have your trailer with you in your parking space. Many parks, including state and national parks have additional parking just for trailers and boats. I watched a guy at a KOA in West Yellowstone that had it down pat. He had a 43' motor home with a large enclosed trailer. When he pulled into the campground his wife went in to the office to register. While she was doing that he go his Jeep out of the trailer, disconnected the trailer from the MH and hooked it up to his Jeep. He then drove the Jeep to the overflow parking area and dropped of the trailer. He then went and parked is MH and all was well.