To ensure you don’t overspend at the Black Friday sales this week, start out with a strict budget, Consumer Reports advises. Whether you do most of your holiday shopping in-store or online, decide how much you’re ultimately going to spend, and stick to that number. If you are not sure that you’re getting the best price on something, move on to the next web page or display. And if you can’t resist using a credit card to overspend, only carry cash to stores instead. Finally, check retailers’ return and exchange policies on Black Friday items to avoid paying a restocking fee or having to keep merchandise you don’t want.