Every busker in London is required to have a busking license from the city council, in which they would like to perform. A person from with a Hackney license is not allowed to perform in Westminster, for example, unless s/he has a Westminster one as well. Buskers of Covent Garden, however, is required to receive a license from Covent Garden even though it is located inside the Westminster Council. 

Performers don't pay any fee to the management company when becoming a performing member or they don't pay any share from the donations they receive.

I have observed and been informed that there is a strong sense of community both in musician and non-musician members.

There is system of representation at place. Singers, instrumentalists, and non-musicians have separate representatives. When an issue arises inside a community, they first interact with their representatives so these representatives could talk to the mangement company if necessary. There isn't a top down governing system at present; the performers are very communicative and considerate to one another and try to maintain a self-governing system. It has been mentioned couple of times by different performers that they are really appreciative of this opportunity.

There are permanent members and substitutes(or freebies as they call themselves) in both groups. For musicians, there is not too much circulation among performers, i.e. freebies becoming permanent members, because there is not anybody that has stopped the performing in the permanent list. There is an interesting categorization: if a singer cannot make it , they could only be replaced by a freebie singer but not an instrumentalist and vice versa. On the other hand, non-musicians have a ballot among all of its members, and a permanent member last week could easily be categorized as freebie next week.