The MDF buildings in this post are from Sarissa, Colin at Charlie Foxtrot models, and eBay. The outbuildings, Greenhouse, and the tractor are just a straightforward paint job, whereas the bigger buildings have been upgraded with filler, cardboard, and coffee stirrers before painting and weathering.
The high and low walls around the farm are scratch-built by me.
The farm buildings and base I got the idea and was inspired by the excellent model made by Joe Bilton. Check out his work in the last couple of issues of WSS magazine or you can see his work on Twitter.