Nice recap on your series to date.
As far as the value of a project, there are many ways to try and figure that number, but most try to include hours (labor) (and to set a value on what your time is worth is a whole new ball of wax), materials (wood), shop materials (blades, sprays, etc), overhead (if you have it, rent, electricity, etc.), and what do you want for a profit margin if you are looking to run a business. That is just a rough start to the process.
Not an easy question to develop an answer. Keep pressin' on, for a lot of us the joy is making something and giving it away, at least for this old man.
Al