In the recent 2 years my wife and I aggressively paid off a lot of debt in credit cards (leveraging some zero-fee, low fee balance transfer and using the money from sale of my stocks and our salaries).
She still has student loans and just her salary is not enough to make all the payments herself in a reasonable time. For practical purposes I contribute heavily towards paying down the debts and as and when she has surplus she pays off some too.
Situation: She has subsidized loans which are in deferment. She also has un-subsidized loans on which she is paying interest (about $100 to $200 per month) to keep from the principal going higher.
In my opinion, this is money down the drain but for the longest we had other debts to worry about (plus student loans don't affect credit history/scores?).
Aim: To start paying off the student loans too with the least interest possible. We don't have cash reserves to pay off at one go and so we are looking for a low interest loan or even a balance transfer(?)
More context: Upon my suggestion about 6 months ago, she approached First Republic Bank to see if she could refinance her loan to pay off her un-subsidized loans. They had loans starting 1.99% APR for a period of 36 months and the payoff portion of the un-subsidized loan is about $14k ~ $20k. They asked her income and her current debt (which as of then was $8k in credit cards) and said to reduce her debt and then apply.
Constraints: At that time I had close to $30k in debt (some balance transferred from her credit cards) and I didn't think of an alternative. Now my debt has come down to $10k and my income is high enough but because of some problems with her house she incurred more expenses that she had to put on a 0% APR card. So if she calls again she has more debt than before.
So I am thinking if I can apply for refinancing her loan and make low monthly payments thereafter for 24-36 months. Is this doable? (Can I do this on her behalf?) Do I have to apply for a joint loan? (I am concerned that her income and debt situation may not help our cause unless they'll consider total income to total debt.)
Are there other ways to achieve my aim?
Residence: California, USA Loans were perhaps taken when she was a student in Georgia, USA
PS: The title says wife but I am happy for answers that could apply to an adult sibling or even a friend.