Great idea but off the top of my head I'm not sure how I'd do this. I'll give it some thought and do some research though.
I've long thought of writing a separate program to keep track of our stashes, including purchases, swaps, etc. I still haven't given up that idea but it would require months of intensive programming and help from my DH for some of it and so far I don't have his support since we see no way to monetize it. He has other potential income sources to program so obviously chooses to spend his time on those. If I had my way I'd write it and give it away but I suppose that's not practical, at least not until I no longer have to work.