Road Bike Purchase, up to £1000

Unless you're prepared to shell out for replacement chains/cassettes/cables/tyres/brake pads/other miscellaneous components that have worn out, on top of the cost of the bike itself, I wouldn't bother with 2nd hand road bikes.

Eh?

I paid £1,200 for a £3,000 Cannondale SystemSix which had less than 20 miles on it- it still had the anti-scratch stickers on frame and mechs that the shop put on.

I put pedals on it, that was the only additional cost.

Second hand is an extremely good idea unless you have zero knowledge, and even then one of us will help in exchange for making us laugh and/or beer.