The Land Registry has a record of ownership for all land and properties, a solicitor or conveyancer would check that to make sure the seller had the legal title to the property. They would also make other checks to make sure there aren't any imminent building projects, such as a new road being built 50yards from the house. Incidently, even if you did give someone the cash in person, they would have to pay off the mortgage before the lender would release the deeds, so they would not have the title deeds with them. It is possible to do the conveyancing of property yourself, but I think people who do, do it for the challenge rather than saving money - a solicitor would charge a few hundred quid but I would say this is one thing in life it is not worth trying to save money on!