you could do the 2 dollar walmart job. just buy a can of black spray paint from walmart and spray it on the car, just remove the hubcaps. in a few months it will look like crap again.
imo remove the hubcaps, use a steel wire brush, some 50, 100, 200, 400 grit sand paper, or maybe just try 150 and 300. then use some rust remedy. they have it in spray cans and it turns rust into a black primer and will prevent rusting. then a few coats of black paint. you can get some high temp wheel paint and clear coat it if you want lasting results, 1-2+ years. It will be a 50 dollar job and a weekend. sanding and drying will take a while.