I've no busked in England,apart from one short stint, too many young teens shouting oscenities or looking for trouble. I busk in Ireland a lot. Do you really get other buskers coming up asking for your spot!? how rude is that! Never happened to me and would never do such a thing. I'l often stop and say hello to another busker, ask him how he's doing, if doing well. I'll go away for a couple of hours then come back to see if the spot is free. Rules? Well, can't say I like the idea, it's such an informal activity bulsking and I find Buskers usually respect each other enough to follow an unwriten code of good manners.
I always have about 7 songs ready, couple of reserves just in case,you'll rarely get folk stopping to listen for more than a few songs. Pics with passers by, happens a lot in Ireland and I've usually found a request comes with a donation, if not I don't mind, ut I do more for fun than as an income. It'd be good to have some good location tips exchanged on here. I'll kick of by suggesting, top of Butterslip Lane in Kilkenny city, Main entrance of the Busares Bus station in central Dublin, and the walk oppisite The Rover Court hotel, in the shade of Kilkenny castle in Kilkenny city, all good earners and lots of tourist, Irish songs go especially well