I also use velcro (industrial strength) it works very well. In the bathroom, I made a toilet paper holder using a plastic clear container. I placed it on the ceiling...it is kind of funny but very useful and out of the way. Here is a picture. I can make you one as a trailer warming gift if you would like
I added a kleenex box by the dinnete wall. I discovered that for the fiberglass wall areas the command water proof (designed for showers) hooks work wonders.
I am so happy for your new trailer, congratulations!