Quick price-history check that saves me from fake deals

I’ve noticed retailers cycle shallow promos, so I sanity-check with the 90‑day median on Keepa and only buy when current is at least about 12% under it - for example, the LG C3 55" hit $1,099 this weekend vs a $1,249 90‑day median, which lines up with pre‑quarter‑close markdowns. If you’ve found a better threshold or a tool that nails seasonal dips, I’m all ears.

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I switch to a 180‑day average for anything seasonal and set a Keepa alert on the Buy Box ≤ average −15%; it filters out coupon-inflated list prices and 3P noise. That snagged my Samsung S90C at $1,199 two days before Prime Big Deal Days when the 90‑day median was still around $1,329.

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