1. Some sort of large clip. A bag clip or a binder clip, something along those lines. If you have a room that faces say, towards the west, the light will beam in through the curtains that cover your sliders like a death ray. You can clip the curtains shut.
2. Closet sweater hangers. This will give you some nice large shelves to store things.
3. Paper fold up boxes sold at Dollar Tree. This gives you several little places to store things and put them up instead of having the items scattered about.
4. Pop up laundry baskets. Put them under the sink or in an out of the way corner and toss your dirties in as you go.
5. Safety pins. Do I need to say more?
6. A small kit with everything medical you can think of: constipation, diarrhea, sunburns, other burns, headaches, body aches, colds, blisters, cuts/scrapes, and hurt feelings. Mine usually has sample or travel size of all of the above and the bandages are taken out of their boxes before packing. Most of it comes from the Dollar Tree.
7. Extra hair accoutrements from the Dollar Tree or similar, especially ponytail bands. They are useful for so much more than hair. You can close all sorts of things securely. Much better than rubber bands.
8. Coffee in premade packets along with whatever you take in your coffee.
9. Clorox sanitizing wipes. Not only are they good for cleaning off surfaces, they are better than Tide pens at getting away stains off clothes. Don't bother with the travel pack. Buy a bottle and put a good wad of them in a good zippered ziplock-style bag.