Many hotels are able to secure and reserve your accommodation with a credit card number, however, the hotel is very likely to charge you if you have to cancel at the last minute.
Smaller establishments may accept your reservation without a deposit, but they reserve the right to give away your room if you do not arrive before 18h00.
During busy events and trade fairs some hotels, which do not accept credit cards will insist on a deposit by international fund transfer. Banks in the UK will charge a fee of £5-15 if you want to send money to Germany.
