I was threatened by a customer years ago.
He was a middle aged single guy who Iived with his elderly mum. I had done a first clean on their house a month before, and he was nice as pie (chatted and gave me a drink.)
The following month I'm just about to start on his house when he says 'hang on a minute, there's a problem'. After asking what's up, he tells me that he doesn't want me to clean the windows, in fact goes so far as to say to goes that I didn't clean his windows last month and doesn't know why I am on his property now.
I tried to explain that he had asked me, and I had cleaned them last month, and that he was happy then and had asked me to call every month. He wasn't having any of it though, and even his mum backed him up that I had never cleaned their windows, ever! He then told me to 'go away' and never come back around there again, or else!
I politely, but firmly told him that I certainly would not darken HIS door again, left and started on his next door's neighbour's house!.
The lovely old lady next door had heard the conversation, told me he was mentally unstable, and begged me not to take any notice of him. I reassured her that I was going nowhere, (of the 24 houses in the close, I had nearly all of them) and he would have to do much better than that to scare me off!
Thereafter he used to scowl at me whenever he saw me, but never said a word!
John