Well the prices were really reasonable before 2020 halloween and then it was manipulated by the rich playerbase. RP prices, Vanity prices everything started to increase after that just cause a specific group made too much pokeyen.
That's the thing, the ingame grind has been nerfed to a certain level where even super grinding won't get you the old vanities even after literal years.
They will keep nerfing it, so the best way to get the old vanities is sell your house, kidney and buy them.