I don't want to high jack this thread, so kick me out if need be. I have the same question about a hammer drill. I want to be able to secure vending machines to concrete floors, so I don't need anything very heavy duty. I wouldn't use it often, and I'd like it to be cordless, assuming the cordless version won't cost me 5x what a corded will. I'm under the impression that a hammer drill isn't much more than a regular impact, but I've never used one and wanted to ask here first.