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Browse credit cards from a variety of issuers to see if there's a better card for you.
See my signature link for my 11 rules to rebuilding.
Based on my experience, FICO wants to see you with 3 credit cards of your own -- secured Discover is a great addition.
Eventually, for the most FICO points, you actually want 5 credit cards of your own, but you get dinged going from 3->5 for a period of 12-24 months. The first 3 cards you get are "free" points.
Once all the cards and loans appear, you may see a nice boost -- you could get anywhere from 30 to 60 FICO points as long as you manage utilization using the AZEO Method (in my signature link).