I've found and booked inexpensive hostels all over Europe several times through this online service . http://www.hostelworld.com/
There are rooms in most major cities for $10-20 a night.. it's prime vacation time now though so I don't know about availability but you can try.

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Tomas, Sweden
1966 Mercedes Benz 230S with OM617.912, automatic. Disk brakes from W108
1983 Mercedes Benz 300TD grey, OM617.912 and 5-speed manual
1983 Mercedes Benz 300TD blue 7-seater, OM617.912 and 5-speed manual