Can a couple live on £40-50k in London?

My boyfriend and I are both from ireland but have been living in Toronto for two years. Our visas are up in October 2015 and we are looking into the possibility of moving to London, UK. We choose London because I work in fashion and hope to gain a better future for myself career wise if I move there. My boyfriend's company can move him there also. We figured we'd be lucky to be making £20k each especially at the beginning. We are optimistic as my boyfriend's company is quite decent in helping their staff move up to higher positions. I work freelance so my pay will go up and down every week but I'm good at hustling and I won't let it go below £400 a week as I do plenty of odd jobs like nannying, promotions, personal shopping. I'm just looking to see if anyone else is in sort of the same boat as us financially? What neighbourhoods would be our best option? Is there any artsy neighbourhoods that are on zone 2 where rent would be £800pm? Or less even? What's property tax and how often do you pay it? What bills come with an apartment usually? We live in a condominium in Toronto and our only bills are wifi and electricity which comes to about $140pm. If there was anyone here that was also a freelancer like myself I would appreciate any advice. Is it possible to walk around in most neighbourhoods? I sometimes walk for up to 45 minutes if I have time to save on public transport. I don't really wish to live pay check to pay check, we would like to save at least £70-£100 a month for our uncertain futures. We are both 27, no children and are quite used to city life so we know we won't be living in luxury at least at the start. I can only hope I get a lot of fashion work and I won't have to live on this pay for longer than a year! Any other poor artists out there? How do you live in London? Young couples where do you live?