Claudemir, your friend is very lucky to have such admiring clients. In today's day and age where instant gratification is almost expected, people often are baffled when they hear how long it has taken an artist to paint something.
John, I find it great that you set a time line and try to abide by it.
Someone once told me that the painting let's the artist know when it's done. Hmm, that seems to leave many artists that are hard of hearing, because there sure is a lot of unfinished work out there. Don't you think?
Joking set aside, I believe that there is truth to this statement , because if one knows the fundamentals of drawing and painting and truly follows the procedures of preparatory work, proper layout and paint application, time can be saved from the onset, resulting in a fairly decent painting. Then it becomes a matter of the artists individuality and his/her "critical eye" , weather to push further or leave it be.
Creating art is a curious thing. One person can create something beautiful in a day, another in a week and yet another in a matter of months.