Hello
Dahon have others models of "big folding bikes", like the Expresso. It's heavy, low end components, but one of the most affordable "correct" 26" folding on market. Cheaper must be, i think, a kind of lottery because they are for a majority copies of montague bikes, made in china without quality control.
But it's possible you could find a good model in these prices.
These big wheel folding could be a good base for upgrading and have a honnest touring or sport road bike, like here:
Of course the big problem is the place they take, compared to a 20" folding...