I was thinking about it because I would like to give my mantis a bigger home when I get back to Detroit, he's a larger species. A 10 Gallon tank ($12), 10# of live sand ($20). A nice piece of live rock ($20), a powerhead such as a Hydor ($20), a heater ($15) and a top ($20) is all you need. No light required, just daylight from the windows would suffice. You're talking $120 to keep the lil guy. Like I said, I spent $40 on my small species so you're ahead of me!
My current mantis I spent like $60 I think, rofl.