Need insider information on the best place to live in London

I'm currently looking for a place in London with a friend i was wandering if anyone could help...

I need to know:-

Where are the good places and where are the worst places to live and why?
What places are good for unsigned live music?
What are the good agencies for extra/modelling/promotions work?
What employment agencies for general work are recommended?

If anyone can help i would really appreciate some guidance :-) !!!!

Cheers

Rhi
xxx

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