The machine may work just fine for you but the flux core wire is not meant for thin sheet metal use. The MIG process uses a shielding gas and a solid wire. The flux core process, while meant for welding thicker material, can be used for sheet metal but the wire size will have to be reduced and the welds will not be as clean. Can you make it work? More than likely. So in answer to your questions.
1. possibly but you get what you pay for. I bought a Lincoln 135 machine and got a two year warranty. You machine will have little resale value once you are done.
2. No, you can get it at Home Depot/Sears/Ace Hardware.
3. Welds will need to be cleaned prior to finishing. Very difficult to weld thin sheet metal using flux core compared to MIG.
4. It is a wire feed welder. It will perform MIG operations IF you hook up a inert gas bottle and a regulator. You do not need TIG for body panels.
