I've got a Dahon Espresso I bought off Ebay cheap about a year ago for my wife which is mostly fine, if a little slow for my own tastes, except that I find it impossible to fold or unfold. I took it to a bike shop recently who speculated it might have some rust issues on the inside (it had been sitting inside a cupboard for a good few months over the winter), but when I picked it up they told me even they had struggled to fold and unfold the frame. I had a go at it myself on the spot and, as usual, struggled to so much as part the frame even slightly once the locks were off. So now I've got it at home, and at some point later I'm going to have to have a go again and see if I can unfold the damn thing.
It's clearly not a rust issue, partly because I struggled to fold it when I first got it, and put it down to stiffness. But I see from this forum there are people who can fold these things in thirty seconds or less. Twenty minutes of huffing and puffing is more like it where I'm concerned, and that's assuming I manage to get the thing folded or unfolded at all. Any ideas, or have I bought a lemon?