Most hotels, these days, will not allow you to book a room with cash.
They insist on card payments.

From the guest's point of view, the down side of this is that charges
could be added to the card without the cardholder's knowledge or
consent and he only finds out about them when he gets the bill.

Are there any ways to avoid this happening by using a pre-paid card
where the cost of the hotel room is all that is available?

--
Alasdair.