gutter boundary overhang like that when bought

Why do new build developers build garage walls right on the property boundary line so that the gutter and drain pipes over hang onto the neighbours property? Assume they’re all compliant with building regs but does it not cause issues if any maintenance needs doing to the wall, gutter or drains...

Hi We bought a house one year ago which we're having major renovations done on. Since we moved in they have complained that our gutter overhangs their boundary even though it was like that when we moved in. Do they have grounds to complain if they didn't complain to the previous owners? They...