ooxs wrote:I don't recommend this move, they might close her account (i know of one case). Find a bank that allow joint account like chase, which might be more beneficial to you than being an authorized user.
+1 Because AMEX requires the additional cardmembers' SSN, they will find your account and they could find a way to close the Mrs.'s account. $31,500? They are one company I would not want to cross.
If you want to shop at Costco I would recommend using your debit card or seeing about getting an AMEX through Barclay's, First National Bank Omaha or GECRB (Dillard's AMEX)-if you have not also burned these companies in your bky and if your credit is high enough to qualify.