Absolute scumbags,
We had something similar a few years ago when only certain things were taken leaving plenty of other valuable items.
The worst part is only Friends knew about the items taken and where they were stored (at home), things in the way were moved and then put back neatly afterwards on a weekend when it was known we would be at a show!
Had to be someone we know but we never found out who which is a shame as you then doubt all of your friends.
Hope they die slowly of some malingering disease.