Its always best practice to avoid using any credit cards during a refinance or purchase process. The refinance can take anywhere from 30 – 60 days. If you do need to use your credit cards, always ask your current mortgage professional if using the credit card will affect your new loan. A new balance on a credit card will create a higher monthly payment expense. This could disqualify you from getting your new mortgage. Not to worry though as you can always pay off the new debt at close if you have the money to do so.