One problem with sharpening the blades is it moves the position of the edge. Eventually the edge is removed from where the sharpening magic happens....
The "subtle differences" comment is interesting. For some situations there are chisels in my accumulation that just feel better than any of my other...
If a contractor goes along with your idea, what is to keep them from buying the flat packs from your supplier and cutting out the middle man (you)?
...
So far I have given away 11 saws to seven different people. These are totally free, and that includes shipping. Why don't I at least charge shipping?...