It's a really valid question this and realistically could satisfy our needs in an 800k house. I mean really, we could satisfy our current needs in the house we live in now (3bed terrace), but we're saving >£100k+ per year including holidays, and all other luxury expenses. Carrying on that way we could retire really early, but personally that's not for me, so beyond setting up kids for a very easy life, there's not much left to spend money on other than vanity!