i REALLY hate to post this but ive been browsing the hundreds of pages of this and i cant find an answer.

i bought an orbital skilz sander/buffer tonight. i hope itll make the job a little easier. plus my girlfriend is wanting me to buffer her car. i also got the foam brushes, tray, rustoleum in a spray can for small primer areas and door jams, tape, etc. all i have left to buy is the brightside, penetrol, mineral spirits(i couldnt find 100% mineral spirits at walmart), and a roller.

my question is, is there a specific brand roller i should be getting. i see everyone saying something about a 4 inch roller. the ones i saw at walmart were 9" smooth surface foam roller. they were sold individually. i didnt think they were what i needed to i didnt buy any. do i need to go to home depot/lowes to get the right ones? if someone could give me a list of companies/product numbers thatd be great.

thanks.