What's the most outrageous retail markup?

@Nozinan So far-thankfully-just a virtual wall.

Saw a Macallan exceptional single cask first bottling- 2017/ESB-9182/01 sell for £22,500.00.

One that keeps annoying me is that it seems (!?) that the Redbreast 12 vs 12 CS is almost the same price, at least the difference is not huge, elsewhere in the world, but in the UK the difference is £37 vs £86!