I try to use mostly stash. Some of my yardage is several years old, and I don't have a clue what I paid for it. Most of it was sale priced. I have batts that I have purchased on sale or with coupons over the past 2 or 3 years. My old brain can't remember what I paid for that either. As to time spent? I don't think I can start keeping track of that. A lot of my quilting is hand work. A min. or 2 here another there etc. Keeping track would be so worry some to me!!