All the busking experience I've ever had was opening up my fiddle case and playing at the local Farmers' Market. At first, I didn't hardly make much worth counting. But the next season I think the word got out that there was this fiddler downtown playing at the Market. Tips got better. And I discovered that Saturday mornings were the richest pickings of all. People used to stop me on the street and ask if I would be returning to Farmers' Market next year. I learned from my experience that longevity is the important factor in how much you take in. The longer you play at a certain location, the more recoginzable you'll become, and you'll develop something of a following, so to speak.
Jim