547 is pretty low, but I've seen lower. Look at my signature below. As far as how long it will take to raise you're score, no one really knows. We need info. What's on your CR? Where did you get that score? What baddies do you have? What postives do you have?
Start with pulling your FREE CR's from (ACR) annualcreditreport.com . they tend to have more info on them, then ones from a 3rd party. The CR's from ACR, come directly from each of the CRA's. You can pull 1 Free CR from TU,EQ and EX every 12 months.
Save your money and Don't Buy the Scores, they are what we call FAKO's.