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Advantage scores that Credit Karma are about useless. You need FICO scores for a real window to your creditworthiness. CreditCheckTotal.com has a $1 trial in which you can get your 3B FICO scores and 3B credit reports. You can use the $1 trial as much as you want. Just be sure to cancel the trial or you will be charged for the monthly subscription. Also, Discover.com/free-credit-score/ will give you free TransUnion FICO Scores.
I would start with Discover and American Express. These credit card companies are not averse to thin credit files and many members have had good outcomes when applying. You can check their prequalify sites if you are really worried about qualifying. Just keep in mind that even if you are prequalified, you are not guaranteed approval and conversely, if you are not prequalified doesn't mean you won't be approved.
Ultimately, what a person needs to improve their FICO scores and build credit are three open credit cards (secured or unsecured) in good standing and one open installment loan in good standing such as a car, home, student, personal, share secured, or credit building loan. This combination is what the myFICO score theorists here have determined is what you need for optimal credit building and FICO score. You can have more CCs and more installment loans, however, this will not increase your FICO scores.
If you not able to get unsecured cards then perhaps you should consider applying for secured CCs. IMO, Discover it Secured is one of the best-secured CCs for poor credit, bad credit, and no credit applicants—and one of the best gas CCs you can get with bad credit. Disco offers 2% cash back at restaurants and gas stations (one up to $1,000 in combined purchases each quarter) and 1% cash back on other purchases. You’ll need an up-front security deposit of at least $200 to apply for the Discover it Secured Card.
Capital One Secured CC requires a refundable security deposit of $49, $99 or $200 based on your creditworthiness. Make the minimum required security deposit and you'll get an initial credit line of $200. Plus, deposit more money before your account opens to get a higher credit line. Get access to a higher credit line after making your first 5 monthly payments on time.
Bank of America's BankAmericard Secured CC is designed to help establish, strengthen or rebuild credit for an annual fee of $39. A minimum refundable security deposit of $300 is required to open this account. Your maximum credit limit will be determined by the amount of the security deposit you provide, your income and your ability to pay the credit line established. If you provide a deposit that exceeds the calculated maximum amount based on your ability to pay, a will be returned to you for the difference. BoA periodically reviews your account and, based on your overall credit history (including your account with us and other credit cards and loans), you may qualify to have your security deposit returned. Not all customers will qualify.
An installment loan will have its greatest impact on your FICO score when the amount owed is at 8.9% or less of the original amount owed which is usually in the final months before the loan is paid in full. If you don't have an installment loan you can check into Self Lender or a Share Secured Loan at a Credit Union.
Keep in mind, building credit is a marathon, not a sprint. It involves demonstrating to a potential creditor that you can handle credit responsibly. If you have open, active credit accounts that are being paid on time and pay all of your bills on time every time, apply for credit only when you actually need it and use credit cards sparingly maintaining low credit utilization, then you’re going to earn and maintain great credit scores. It would be impossible for you not to do so. This is the fastest way you can build good, solid credit.
@Anonymous wrote:
Thanks to you all for clueing me into creditchecktotal. And the wealth of knowledge you all shared on how to build a strong profile. He just signed up for a trial on creditchecktotal to see his Fico scores.
His Fico scores are:
Experian 772
Transunion 791
Equifax 772
Utilization is at 6%
Oldest account is 7.2 yrs and average is 4.9 yrs.
We’ll take a look at the discover and Amex offerings and go from there.
GOOD LUCK 
please let us know
@HeavenOhio wrote:
@Anonymous wrote:
We’ll take a look at the discover and Amex offerings and go from there.Check the pre-qual tools at Discover, AMEX, and Capital One. Mostly for giggles, also check Chase.
Chase disregards authorized user accounts, so I wouldn't expect anything from them. It was posted recently that AMEX also disregards them. But a pre-qual might indicate that his profile is OK.
I think Discover or possibly the Captial One Quicksilver would work. Discover likes thin files, and Capital One specifically says that they consider AUs.
I don't think there should be any need for a secured card or even a starter card. But some banks are probably out until he has some history of his own.
@Once again, Great Advice from @HeavenOhio !