The work was done well as far as I could tell. However you dropped the ball between cleaning the moss off the roof and spraying it. In fact you sent me a bill before the work was done! Nevertheless, you were polite and apologetic about that so eventually the work was completed.

“So sorry about the office email invoice error Mrs M. but glad to hear you appreciated the quick phone call we made explaining the mistake!  Looking forward to re-treating your roof when the warranty ends in 24 months :)”  -TRT