Exactly what I would do! Put one tote of fabric on a shelf and wait to see if there are problems before unloading the rest.

Lucky you!

I would take over the basement, providing that there is sufficient lighting, good ventilation, and good heat/AC. I used to having my sewing area in the basement when I lived in CO. It was great because I could really spread out. Now I am in a spare bedroom just slightly larger than yours, and I wish I had more room. Please post pictures of your space once you decide and are set-up.

definitely to the larger area.just keep things on shelves and up high-just in case