I have a neighbour who is tormented by kids kicking footballs into her garden. There is a grassed area, surrounded by 3 roads and one side of her fencing is on the remaining edge. There are legal conditions on the area prohibiting any ball games or cycling. Signs have been badly damaged, the company who owns and manages the area has taken them down and basically given up. The residents all contribute to the maintenance of the area. Her GD when in the garden has been struck by balls, cups of tea knocked out of hands, fencing broken. Door bell can go 5/6 times after school, kids wanting the ball back. Last year it was so bad during school holidays she starting telling kids a ball will only be returned to an adult to make sure the ball actually belongs to the person asking for it. (Older kids usually send the youngest kid to ask but the ball doesn't belong to them.) Of course adults moaned about having to get of their a..e and go get the ball. Some said they didn't have time to collect a ball, no thought about the neighbour who was having to answer door then go get the ball from garden. Got so bad the police became involved giving advice that balls should just be handed into police station say once a week and people informed to collect there. Stopped a lot of the problem but neighbour always on tenterhooks it will all start again with good weather and school holidays looming. Some folk have very short memories. Yes, you are obliged to return a ball, but there is no stipulation on method or timescale. If any damage incurred, whoever owns the ball is responsible for recompense. I had a brother who was a professional footballer, played twice for his national team . Never allowed a ball in the garden, always taken to a park or allowed on his own when older. Dad always said no one can play football in an average garden, they can only kick a ball and those who do that, usually have very little control of the ball. My two sons were never allowed to kick a ball in our garden. And this is not a deprived area by any means parents are just lazy - out of sight - out of mind and not bothering them! Try my neighbour's tactic, balls returned at end of day or end of week.