We get asked this quite a lot, especially by customers who aren't bringing their goods in themselves...
We need you to come and sign the contract in person, so that we can take a photo of you (for security purposes) and witness that your photo ID is valid. Although this might seem inconvenient, when you think about it, you wouldn't want just anyone to be able to ring up or walk in and take out a contract in your name, without us verifying that it's you and all completely above board.