As I did this one I took lots of step-by-step pictures.
This is their Dark Age Watchtower that I picked up recently for a very reasonable £7.50. It's much smaller than the ones available from 4 Ground, but for the skirmish size gaming I mostly get up to it's perfect and as I like my scenery to have a small footprint fits the bill exactly.
So what do you get in the bag?
A big pile of lazer cut MDF. All smelling slightly burny. There are no instructions. I'm not sure they're necessary to be honest, if you can't work out how to put this together you probably shouldn't be handling sharp modelling knives. Or indeed any sort of knife apart from those bendy rubber ones.
That said there were a couple of points when it might have been handy to have things spelled out - do this first or this bit coming up will be trickier then you imagine - that kind of thing.