I think the seller is a bit, shall we say, optimistic with their valuations. I spotted an ordinary Raleigh 3-speed the other day in North London which the seller had priced at £980! It's the sort of bike people find left behind in lock ups and domestic garages by the previous occupant when they move in!
That said, buyers don't do themselves any favours either. Just this week a very ordinary Raleigh "racer", with a Carlton type wrapover frame - so probably plain gauge tru-wel tubing - went for £160!.
It had clearly visible blemishes and looked like a station bike or town centre shopping hack. I might have been persuaded to pay £25 if my arm was twisted very hard.