The only camera of real value is the Leica. At least here in Europe. I recon you should be able to get at least €500 for a set like that. Although you might also reconsider keeping the camera and trying it out yourself. Not many people get a change to work with Leica gear. It's really nice stuff, hence the high price.

The Minox and Rollei aren't worth much. I'd say garage sale prices...