Rent: My touring bike

With regards to the deposit, why not take something other than cash? Debit or credit card?
Something the renter will defiantly want to come back for... Otherwise you may have just sold them your lovely tourer for £100.

Why not both? Taking the card could mean nothing to some people. I personally have a bank card which is never used.

I'd say you'd want:

£100 deposit
confirmed home address
debit/credit card