My experience is that sales are unlikely to cover a component you want anyway. If they are right around the corner, then sure why not, but otherwise just enjoy your new computer sooner rather than definitely waiting to maybe get a deal.
Do check price history though to see if something you're interested in is currently overpriced or regularly on sale.
You can look on pcpartpicker. They usually have a graph holding price history. You can see when it was last one sale and make a choice to wait or buy then. Note: I would suggest against buying parts only on sale as if you buy, say a mobo and don’t buy the rest and you can’t test it. That might leave you stuck trying to do warranty claim instead of a store return. Good luck!