My take is a bit different, but the answer is the same.
DO NOT buy this trailer. You're buying something from a relative that either she has no clue about or is lying to you about. Don't do business with her. You found a trailer floorplan that you LOVE - go on the internet and look for non-salvaged, clean titled trailers with that floorplan. Buy from a stranger before you buy from a relative. Once you see how much the trailers are really going for, call the campground and ask about fees for permanent sites. Then buy a decent trailer from a stranger and have it towed to the site.
