Storage space wanted

I am moving back to my parents before going travelling for a year and I am looking for somewhere to store some of my stuff.

I have looked into storage facilities but they are expensive.
I'm not really sure what I'm looking for....a garage that isn't used, loft space...

It would be for about 18 months and I would be willing to pay something...and provide beer. :D

preferably in the oxfordshire area.
Anyone got anything along those lines?

Louise