where to buy preowned macbooks (uk)

Hi guys i'm trying to buy a black macbook with applecare ive been looking on
ebay, gumtree,craigslist and the loot wanted to find out if there was anyone
other places to look i'm based in London

I've looked at refurbished macbooks but the only black book i saw was over
£800 the new macbooks are great but even with my student discount too
pricey

Any help or suggestions would be great

rema.

thanks for the info wibble.