Interest!

I decided today to find out just how much interest is on every account that I have outstanding, wait for it:

Credit Card (Kilimanjaro) - 18%
Credit Card (Middle Amount) - 23, 5%
Credit Card (Lowest Amount) - 21%
Shop Card (Highest Amount) - 23%
Shop Card (Lowest Amount) - 21%
Vehicle Finance - (14%) (LOVELY)

The lady at the varsity collections place didn't seem to understand English too well so I am still waiting to find out how much I interest I spend there. Will keep you posted.

I need to do some homework to figure out if I must the smallest amount or the highest interest amount off first. Any ideas?