Ok, just got back from the bike sale:
Despite the rain there were quite a few people there. As predicted most bikes were Apollo MTBs. There were some better bikes: a ladies bike which was in pretty good nick and a promising steel hardtail (it had been badly repainted so I've no idea of the brand). Unfortunately it was very small - I measured it at about 14.5" (I'm 6'3" so need about 19 or 20" frames).
One guy bought a lot of bikes - I suspect he might have been planning to sell them on. Although I didn't frankly see any profit in what he'd bought.
For a few seconds I considered the tiny hardtail MTB as a jump bike and then thought better of it. (Jumping really isn't me, I'm very much a both wheels on the ground XC guy.) It would have been nice to come away with something to put on a turbo trainer (weather being the way it is and all), but I haven't wasted my money on any junk - so that is a good result. Ah well the search continues... right I'm off to waste some time on
Ebay.