Freefaller, I think your numbers might be a little out of date. This
map of average one-bed flats within 1km of a tube station suggests most zone 3's are above £1000. Certainly the case where I am in west London.
I've always lived in zone 3, west London. Started out sharing a house with 5 guys on minimum wage (£13k). Did that for a few years. At that time my girlfriend one-bed flat round the corner was costing her £900 fyi. It's more like £1200 now. We now rent a two-bed flat together quite comfortably between ourselves (I've obviously had massive payrises since then
)
I'd suggest living solo in London is not as peachy as it sounds. Find some nice flatmates and you'll be far more comfortable. It's do-able. There's a lot of normal people out there.