I take screengrabs through the year of products I’m interested in and keep records. So I tend to see when they raise their prices in early November, only to drop it to just above the original price for their Black Friday “deals”.
Really there needs to be changes in consumer law to tackle this. We either lost a bunch of legal protection after Brexit, here in the UK, or the retailers realise they can get away with it. Amazon is really bad at this. So are the really big tech retailers.