Millwallawayveteran1988 said:
Plenty are staying at the A & O place by the sounds of it.
Sold out now thou but this looks a cheap alternative
<a class="postlink" href="http://www.booking.com/hotel/de/djh-jugendga-stehaus-adolph-kolping.en-gb.html?aid=340315;label=hotel-64400;sid=c0f030a04f931db1dc8ad78f76245d96;dcid=1" onclick="window.open(this.href);return false;">http://www.booking.com/hotel/de/djh-jug ... d96;dcid=1</a>
What is an A & O place?
Just a normal youth hostel. Usually you have to be a member of the German Youth Hostel Association or the Youth Hostel Association. Could be that you have to pay yourself a tempory youth hostel membership in addition to the price of the hostel. That happened to me when I first visited something similar in Milan. It seems like there is no age requirements.
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The youth hostel membership costs 21 EUR a year - could be that you have to pay that in addition to the price of the room...
http://www.jugendherberge.de/en/terms/use/index.jsp
http://www.jugendherberge.de/en/hostels/search/portrait/jh.jsp?IDJH=641
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In that link you find an A&O in Dortmund:
http://www.aohostels.com/en/dortmund/dortmund-hauptbahnhof/ - and if I recognize it right there is still rooms in all dates in December...