I'd say, use a site/service to check prices and get notifications when they change. I use psdeals.net (no affiliation or such). There I have a list of games I'm

I'd say, use a site/service to check prices and get notifications when they change. I use psdeals.net (no affiliation or such). There I have a list of games I'm interested in and get an email whenever the price goes down. That is for playstation, but I'm sure there are options for xbox too. Nintendo seems not as eager to do deep sales, disappointingly enough. Deep sales are imho great for those games you hesitate on. On that site, I can also see price history to see what the game normally sells for, or what the common sale price for it is. Meaning, I'm less trigger happy just because I see a "sale!"-sticker.