I'm no expert, but generally what I've read on here is apply for both Cap1s that you're prequaled for. If you do them both on the same day, it only counts as one inquiry. They're both pretty good cards!
From what else I've read here, the most bang for your buck is to have 3 cards. So you'd need to get one more. maybe try Barclay? Their prequal is not quite as straightforward as cap1 though. I guess if you get a firm APR and not a range, it is a good indicator that you'll be approved.
Also you'll need some sort of installment loan, if you don't have one already. If you don't, you could do a shared secure loan from a credit union. You mention being on a budget, you'd have to fork over prob $500 up front, so you wouldn't have use of it for a couple days while the loan processes, but then you get it back and make payments.
After you apply and get the cards, the rest is simple. Use em as much as you can and pay them off!! It sounds like you're in a pretty decent credit situation already though.
As for the credit score checking, I use Credit Check Total. It's pretty decent. You get the first week for $1, then I guess you can call and try to cancel and they'll offer you it for $14.95/mo instead of $29.99/mo. I didn't do this, but I've seen others on here who have.
You can also sign up for credit karma for free, those aren't true scores, but it allows you to see changes to your Equifax and TransUnion reports, and also gives you a general idea what your score is doing.
HTH
