Go to youtube and search on videos, “repairing body panels”, “using a hammer and dolly”, and similar videos will pop up. Craftsman collision repairman can straighten most steel sheet metal panels without using fillers like bondo, there are many techniques, most not obvious, to do this. Example, you should never simply push a dent out from behind. Watch as many videos as you can and you will begin to understand how its done. Generally you only need a few hammers, a dolly or two (hunk of smooth rounded steel), and sometimes a torch to shrink the metal.
Dent doctors use similar tools in miniature to avoid actually removing a panel but the theory is the same.
Pete
