Credit card perks can be very useful and with one or two good cards — you could be enjoying free airline flights, free hotels stays and more.

FICO isn’t the only number used to determine your credit risk — the score that counts is the one your lender uses. There is no single credit score number — the compilers of the widely accepted FICO Credit Score allow lenders to customize their system, so different lenders produce different scores.

This has become less “strange” in recent years, but closing your credit cards can hurt your score.

A credit score is either a blessing or a curse cast down upon you from the digital cloud. A score of 740 qualifies you for the best interest rate on a conventional mortgage. A score under 640 means ugly interest, and a number under 620 makes it very hard to get a mortgage at all.

A few credit score points can mean the difference between a good mortgage rate, a lousy one or getting a loan at all. But take heart — If errors are dragging down your score, you can get them fixed, just in time for your much-anticipated closing.