Lesson #1: never take a commission on something you're never done before. Difficulty: moderate.
I agree 100%!...I mean what are we talking about?...it is not a job like painting Your kitchen door blue or baking a cheese cake... we talking about grinding daggers!....if never done before difficulty is very high.
done several times, difficulty becomes moderate but this will never be an easy job.
I saw fully embelished, engraved upgraded daggers, very expensive pieces but with a blade grind that was not worth a dime....all depending on the level You want to reach....
do one first, develop some respect and then You will ask different questions......