I actually just adopted out my six, haha.
You'll need more than one, I found they did best in groups of three and up.
The Hermit Crab Association is a great website as well, there are tons and tons of crabbers who have helped me out more than once. (: Good luck Vamp! They're really quite fun, really.
edit; Also, I don't think there's such thing as "too big" tank-wise. I had six in my 29gal, and before that kept three in a 10gal.. you need to be able to provide at the very least four inches of wet sand and coconut fiber. (: