Steve- When you get to the pre paint and paint stage I have been successfull getting a pint of enamel and a quart of reducer from the auto paint store.They will pull the paint no. off your car.(I just got both the other day for total $14.At this particular auto store they sell for less than $10 a mix it yourself spray kit. It comes with a clear bottle on the bottom about the size of a baby food jar with a smalller top.On top is a screw on aerosol cylinder. Mix the paint and reducer in the jar and you are set to go. Dont mix more than a inch or so for a small repair,it goes a long way. I havent done this in a while and I forgot to ask the auto paint store what the ratio is.What I do is get a junk piece of sheet metal and prep a small piece of it. Then prictice on it before you go to the real thing.What you should be looking for during the spray is a fine and consistant mist. After it has dried a day or so get a medium compound(paint shop about $10)and borrow a buffer.Lightly buff it out and you will see all those small tiny "hills and valleys" you saw dissapear to a nice finish. With regard to the doors depending how much damage is done I have been successfull both by 1)taking the masking tape and taping off four or six inches at the bottom all the way across the door.The trick is that the end of the tape closest to the repair should NOT be touching the body. So what you have is it the tape farthest from the repair attached to newspaper and the tape closest to the repair folded up like a U. You wont get a distinct paint line when you finish and it will blend and compound out better. Also before I painted I would get one piece of 600 and one of 1200 wet/dry paper. Before and after priming I would use first the 600 and then 1200. Option no. 2 is to mix the enamel w/ reducer and brush it.