I have these great accounts pretty rich neighborhood. Anyways I gave them all estimates on how long it would take to mow ,trim ,and blow off debris. Now that I have been mowing, Ive noticed that it is taking me a lot longer then what I am charging. Is it okay to ask if I can change my estimates? I don't want to lose these clients. I was thinking of writing a letter to each person. Ha s anybody run into this problem? And do you have a cure.