Dusseldorf/Cologne/Bonn (that area) Ski Help

Hey West German (Dusseldorf, Dortmund, Cologne, etc...) Newschoolers, I have a favor to ask of someone in that region. I am (slowly) on my way back to the US from Kazakhstan. I will be in this region of Germany from May 15th-20th and I am trying to find a place to keep my skis (ski bag). Does anyone know where I can keep them that would be safe? If any of you are kind enough to offer your own place for storage. I have a tomahawk plaid shirt (size m) or a jiberish sweatshirt (size L) and a beer as a thank you.