You would be better off investing in a small (Coleman, Igloo, etc.) cooler than a small wood humidor -- especially if you're not going to be around much. Wood humidors require care -- especially inexpensive ones, as the seals are not always good.
In either case, beads will work well for you. But beads will work better in a cooler
A small cooler requires a lot less work and they make great humidors. Just my