You don't need much for these guys. If you are going to reserve him, any chance you can get a pic while you are putting the tank together? Some species benefit from a few little modifications, so if you knew for 100% sure what it was, you could prepare ahead of time.
To really ID one that is difficult you'd need a pic of it's merals. They will be inside the 2nd leg... (or his "clubs" or "s.pear". It's a colored circle. Side shot and top down shot can also be important.
The one on SWF has ocellae (colored circle) high up on his carapace. That's what he IDable by. If the one at the LFS has one up that high, then it's the same. If it's not that high, is elsewhere on the body or is absent, it is not the same guy. But that's easy enough to tell.
They totally need just the basics. A little HOB filter, non glass heater (if it's a clubber), a total dark cave or you'll have problems with molts, rubble all over the place for him to pick through, a nice sand bed, and whatever lights (keep them weak and you won't have trouble with algae and he won't have trouble finding darkness in his cave.)
If it's a spearer similar to the SWF one, I'm going to guess a ciliata. If it's the one like the pic, that would be way cool.