I propose an annual permit application for professional buskers (rather than monthly or daily), with option to sell copyrighted CDs and DVDs. (See my comments re. busking).

As with Andy's comment... an annual permit for professional buskers. This could always be cancelled at any time, but it is strange to have a business rely on a monthly permit system.... I don't know of other businesses that are dependent on a monthly permit. A professional musician who busks and treats his craft as a business is a business.