I don't understand people who say "if I don't sell then I'm going to play anyway".
If you can play without staking then why are you selling? If you can't afford to play (either literally, or due to BRM) then if you don't sell, you can't play. Right?
Why not? It takes some pressure of for such a high buyin.
It's not just a £770 buyin, you have petrol costs, possibly hotel costs, food and drink and so on. So really, you are looking towards a total cost of £900, if not more.