yeah ive had two problems after cleaning gutters, one cust said one of the joins started leaking after i had emptied it. (could have been me, i did rest the ladder on it) i only charged £15 for the gutter, ended up going back twice to fix it so a 15min job ended up taking me an hour! waste of time. going to have to get one of those stand off things for my ladder, so i dont have to touch the gutter with it.
the other cust i fixed a leaking join, (cleaned rubber seal) then a year later it started leaking again, so asked me to do it again, he said your not going to charge me are you? i said yes as its obviously not my fault. he said well im not throwing bad money after good! cheeky git!
a couple of months later i was cleaning their windows in the rain and noticed it wasnt leaking, there was a gap between the gutter and the slates and water was falling straight down. i did tell them, but didnt get an apology.