How do you spot fake lightning deals during Amazon sales?

Im honestly so fed up with these fake sales on Amazon lately its getting ridiculous. I spent the whole weekend trying to find a decent 4K monitor for my home office setup since I just moved to Seattle and my old screen didn't survive the trip. I had about 300 bucks saved up and thought I scored a massive win with this lightning deal that said 45% off. I panicked because the 80% claimed bar was staring at me so I just hit buy without thinking.

Then I actually did some digging and realized the price was jacked up by almost 100 dollars just two days before the sale started so the actual deal was maybe five bucks. Total waste of time and I feel like such a sucker. It feels like every single thing in my cart right now is pulling the same stunt where the original price is just made up. I noticed a few red flags after the fact:

• the list price changed right before the event
• the same item was cheaper last month without a deal tag
• other sellers have it for the sale price normally

I dont want to keep falling for these high pressure tactics but they make it so hard to tell when you're in a rush. How are you guys actually verifying this stuff in real time? Like what specific tools or tricks do you use to spot the fake lightning deals before the timer runs out...