I got one from Lidl last year, just under £30 and very similar to 3rd one in your links. I am very happy with it, good enough for home use, probably not robust enough for a professional bike mechanic/bikeshop. Your Dahon will fit fine, clamp it in using the seatpost. Before the bike stand I used to service my bikes by mounting them upside down in a Black and Decker workmate and clamping the bar stem in the workmate jaws. The work stand is a much better option.
Thanks. I may go for it. I also happen to have some old manfrotto tripod legs and a manfrotto superclamp which both haven't been used in years sitting in my loft. I think I will take a look at seeing if there's any way of turning those into a workstand. The tripod is definitely robust enough to handle my Muno, whilst the clamp is rated to 15kg. Must be a way...