@flipper the general guidance is that places where the average July temp is over 80 °F/26 °C you should place it where it will get at least 6 hours of sun, otherwise mount it in a spot that gets 10 or more hours of sun. The mess… you can get staining on the wall if you mount it on the side of the house. I mean quantity really depends on species and how many take up residence, but you certainly wouldn’t want to mount it right over a seating area or your lettuce patch.(Although the droppings make great compost ammendments.)Generally, I would recommend mounting on a pole, 15-20 feet above the ground with several feet below clear of shrubs etc so they can safely drop into flight.