Answer:
A large oasis in the desert. Come with cash and leave with none.
I'm a word that's hardly there. Take away my start and I'm an herbal flair. What am I?
I turn everything around, but I cannot move. When you see me, you see you! What am I?
What force and strength cannot get through I with my unique teeth can do.
I have a hundred legs, but cannot stand. I have a long neck, but no head. I cannot see, and I'm neat and tidy, as can be. What am I?
No matter how little or how much you use me, you change me every month.