The most expensive was this:
http://www.discogs.com/Vector-Lovers-Graviton-EP/release/1222327
which I paid $30.19 for (I think it was 20 quid including shipping) which I got more for collecting purposes than anything.
The most I paid for a record I actually wanted was $24.53 for http://www.discogs.com/David-Michael-Cross-Future-Man-Cold-War/release/133573
I bought it straight from the label as I couldn't find it anywhere else (for a reasonable price). Strange that people would be selling it for so much when the label still had some.
£25 on a signed copy of Mandy Morton and Sprigguns - Magic Lady.
It's worth at least 10x that though.