I'm going on a road trip this summer for 5-6 weeks with a few buddies. I am going to buy a 15 passenger van and I wanted make some beds in the back for when we won't have a place to stay. I also wanted to fit a small couch in the back. I was wondering if it's legal to have people sitting in a couch in the back of your car. I would be able to make it have seat belts too.