Knock Out Studs Sideways
A sledgehammer works great for busting up studs, but don't take a whack at the middle of the studs—they'll just wobble back and forth and probably bounce the head of the sledge right back in your direction. Hit the studs as close to the bottom plate as you can, but not so hard that you pull out the nails on the top plate—that's a good way to catch a falling stud in the noggin. Hit the bottom of each stud just far enough to dislodge it from the nails that were holding it. Then grab hold of it and pull it off the top plate.
Tear off a roof shingles yourself
Pull Nails With a Nipper
If you're replacing windows, doors or flooring and you want to salvage the trim, end-nipper pliers are a handy tool to pull out brads and finish nails. The rounded end provides plenty of leverage, and if the nail breaks, you can always cut it down flush. Don't squeeze too hard when gripping the nail or you may nip it off prematurely.