Don't......
Get a proper solicitor and impress upon them the need for speed, ideally someone you can go and sit in front of in necessary.
IF........ it falls through or you lose it, so be it. Your solicitor may uncover something which may make it not worth buying.....🤷🏻‍♂️
The bank's repossession sale process is what it is, it's a game, and one to be played on their terms by anyone who wants to play.......
Waaaaay better to lose a few hundred pounds on an aborted deal than be stuck with a property which, for whatever reason, proves to be unsuitable....!!

Good luck

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