I liked the concept here, but tried it out and couldn't figure out how to add the very first thing successfully. I set up my employer's 401k as the first account, and went to add the first investment in the account, but it's a mutual fund not an ETF, which means I had to disable symbol lookup. I had a cost-basis, I had a current value, and I had a count of shares, but you only asked for an average cost-basis and count of shares. I had no way to update the current value. When starting out the first entry should have all three of these. I tried to figure out to update this, but the only value adjustment was via providing a spread (open/high), and I couldn't figure out how to use this to get it to an accurate value. Honestly, it would have been better to have cost basis tracking in a more advanced place and started with current value and count of shares, and then simply update current value on a time-basis.

You can click on the holding, go the Quotes table and add a date, close price