I use a flat pace countertop and cover it with sandpaper. I start with 100 grit and work up to 600. I sand the head surface and engine. Then retorque head bolts to specs starting with a low setting and working up to the full setting. I have never had a gasket problem doing it this way...
Been using ethanol blend gas for years without any problems. Run the fuel real low at the end of the season then refill with fresh at the beginning of the season. The only engine I use ethanol free fuel is my generator because it sits for long periods of time before running. I say do what...
Why are you questioning this, it's only a lawn mower. I would say take it to a body shop and have a professional paint it, sand it, at the least three times, then buff it. Will look better than new. I have found out with years of use on my old Wheel horse that the Rust-Oleum will last...
For a homeowner who doesn't want to spend much money the hand file will work if whey don't let them get too bad. In my shop working for a customers I use an angle grinder. I just don't know how an 21 in. blade can wear to 12 inches, something I would like to see.
I see that the choke and oil has been covered. When you say it starts hard what is it doing? Turns over very slow? You might want to check to see if the fuel pump is holding pressure seeing it starts with starting fluid. There are many things that can cause hard starting?
Buy a cheap mower and you will have to replace it more often. Buy a good brand mower and pay a little more for it with good maintenance it will last for years. My Ferris is going on 20+ years old and still runs and mowes as good as the day I bought it.