I want to reiterate that for the big ticket sets... it can be quite a gamble to wait too long. If you miss out the "new" market price can easily jump $100+. If I know I will buy it no matter what; I pull the trigger early w/ VIP pts and GWP ad-ons... once I have one, then I know I can wait on a deal...which ALMOST always comes near retirement. ZAVVI (The Hut Group) is known for sales on big sets near the EOL. That said, their shipping is an EVEN BIGGER gamble (another reason to secure a nice box NISB from LEGO Shop at Home directly).
ONce in a blue moon a great set goes on sale on LEGO black Friday or end of year. Disney Train, Ninjago City, Docks, large Orange Porsche, CLoud City, etc...can hit 20 to 30+% off. Has not really happened since COvid...but I got like 6 Tantives for like 35% off back in the day.