Is there a way I can generate a report showing what I sold the collection for?
In Statistics, if you scroll down a bit you should be able to see this bit:
It will tally the price sold of that subcollection you’re looking at statistics at.
(note that the screenshot is just random data from a test account of mine, because that would not be a right selling price I think 
Hm yeah, quantity needs to be 1 to actually see something there. You can have the quantity as 1, and set the status to “sold” so it won’t count it as actual books “in your collection”.
Can you give that a go?
That works by setting qty to a non-zero amount.
So that works for you? All good?