"If you just want to know where you stand, you can get a free score and monitor that so if it changes, you'll have a general idea that maybe something's gone wrong on your credit report and you need to pull it, or if you see it rising, you know you're doing the right things," Weston says. "But if you are going to be in the market for a mortgage, you probably want to see the FICO scores that the lenders are going to look at" — say, mortgage and auto scores, which usually can't be obtained for free — "meaning you probably need to buy them."