I'm 26, I make 40K a year. I currently have 4 credit cards with around $3,000 owed on $4,500 limit. My credit card score was 616 last I saw ( a month or so ago). The interest rates range from 8.99% to 18%. I have always heard that you should call you credit card company and ask for a lower rate. How often should you be doing this? How much of reduction in rate should I ask for?