The "black spots" you mention.... I wonder if they're the residue from the shipping covering that I see most KIAs wearing as they come off of the truck?
I was finding spots of that stuff popping up on my car for nearly a year as I'd wash it and dry it. As I said... a little bug and tar remover (or gas/lighter fluid IF you're #$%^& careful!) on a rag will get that kind of stuff off.
After you've got all of the crud off, then get that wax on 'er! :-)
Here's all you need to keep your Rio looking good:
P.S. The name of the wax I use has been changed to "FINISH" 2001.
Good luck!
-SM