Moving a greenhouse?

Depends on the make / construction. If it's your standard run of the mill frame, just drop the glass out, free it from the base and 2 people will be able to move the frame without taking it apart. If like me you're a 'Billy no mates', you'll need to dismantle it into sections and then re-assemble it, you wont get much change from a weekends work.

It's always good to have some glazing extra clips at hand, if you have to disassemble it add some extra bolts into the channels, but it's really not a difficult job.

As already stated, if you don't have to dismantle the actual frame it will save most of the hard work - now is the time to think about whether you would like a higher (or lower) base, and make sure it's completely square and true or you might distort the frame enough to make it difficult to get the glass back in.

I have a council plot, the previous tennants and maybe plenty before them had put 3 stuctures of some kind on the plot all with concrete bases. I am left with the concrete bases which I cannot dig up so it makes my growing space much less. I think concrete on rented allotments should not be allowed.