Step 1: Alice has a problem

When she gets home, Alice sees a stain on the wall that Bob has just repainted.

Alice first takes a photo with her smartphone to keep proof of the mess and its date, which is saved with the photo.

Alice then calls Bob, explains the problem to him, and asks him to kindly drop by her place to see the issue for himself and try to find an amicable solution together. Bob agrees and tells her that he is on his way.