I did one yesterday. Quite expensive.
Quite well off people, I had no problem with thinking they wouldn't pay upon completion.
But I make a point of being paid in full cleared funds before I even get the kit out.
Lady-ok with it-I had prewarned her.
He was not impressed at all. But paid in cash.
Not a good start.
Anyway, they ended up happy with the job.
He didn't come out to check but I made a point of saying to her that I wanted to apologise if I caused any offense and hoped I could be of service in the future.
Stay professional! If all else fails, you can still feel like you were professional, no matter the fall out.