I created a simple excel sheet back when we first bought the car. What I did was created a column for vendor name, part #, price, date of purchase. Then I used the same spreadsheet as a way to break up parts that I needed and put them into groups by project type. Once the parts were purchased I would "cut" those rows and "paste" them up top with the other already completed/purchased projects/parts.
I had the spreadhseet set up to automatically calculate the totals so I would know what the next project was going to cost etc.
I can remember my wife and I going through the Ames catalog and we would color code projects with different color highlighters. Then we would enter in all the projects into the spreadsheet.
Then, we would calculate and project when we would be able to make our next purchase based on pay dates etc. And I know I have told this story before about my wife working FIVE part time jobs simutaneously so we could move forward with our "projects".
Looking back I wouldn't do another project without having the funds/budget to complete the car from begining to end. We went through too many tough times during our nine years of owning our car and seeing our car sit at times only made things tougher.
I feel fortunate to have a spouse so dedicated to making my hobby/dream hers as well. I feel as though we are closer now than ever to actually completing our car and hopefully I'll have enough time with whats left of my vision to see it through (pun intended)!