Welcome Dan'l. Let me speak to the obvious issue - rust. Don't hide it with Rustoleum, you want to take the rust down to gray/black metal by using Axalta (dupont) 5717s, at auto supply stores, about $45 per gallon. At these places you'll find a supply of POR15 paint, but with limited colors (see their website). You cover the rust with this stuff and it works. But I prefer the 5717s; need wire brush and sandpaper and if there any pitting use Bondo over the 5717s. Prime and paint. Search this forum for paints.
Mowers need the most labor. Tedious work but worth it. I brushed on IH white oil base with a hardener to make the finish more resistant to leaf and grass stains. Flipped mower over and coated with POR15 gloss black. Yes, I am a fusspot.
Lotsa luck, Jack
PS: To strip paint I use Citristrip gel. Brush it on, some areas may need 2 coats.