Credit issues will determine a significant part of a Lender's willingness to "loan" you money.   Credit also has a direct bearing on the kind of interest rate you can expect to obtain from a Lender, and just how much you are able to borrow.  It will also help determine if a down payment on any property purchase is going to be required. 

The higher your credit score, the more likely you are to obtain a low interest rate.  This  helps to keep your payments at a comfortable, and affordable level.