Worked example: three chart shapes
Shape A is a long flat then a cliff. For wholesale, a cliff often means someone is clearing stock or a new offer entered. Do not buy the bottom of the cliff just because it is “historical low” — check Buy Box flips and BSR on the same Chilview panel. Shape B is a weekly sawtooth. That is often promo or competing 3P offers. Your landed cost has to clear the trough, not the peak. Shape C is a quiet band with rare spikes. Spikes are poor purchase prices unless you already own the units.
Open Variation Viewer when the URL is a parent. A child with no featured offer can look cheap on a tile and unsellable in the box. Listing quality and Page 1 keyword check tell you whether a rewrite could lift conversion after you source; they are not a reason to ignore a bad chart. Cross-marketplace comparison is extra homework, not a blended price. Chilview: Chrome and Brave, no Seller Central login, no personal info — only product information. $30 one-time Founder for the first 500 users. 3-day trial, no card. User manual: Download Chilview latest version user manual (PDF) from the site.
Keepa still wins if you need a shared multi-year graph. Helium 10 still wins if you need PPC and listing ops. Chilview wins the tab you already have open. Label every fee Estimated. Confirm in Seller Central. That is the whole honest loop.