Is there a way to calculate conversion rate of "presales" vs. "invoiced" revenue? I have tried several approaches. Not sure how a saved search or workbook would even pull this in properly. Maybe I'm thinking of it wrong? I assume it would be the sum of opportunities/quotes and then the sum of related invoices? There doesn't appear to be an native report to calculate this.

Try creating a saved search for opportunities with a formula column that calculates related invoiced amounts using CASE statements to sum invoice line amounts. You can also create this in SuiteAnalytics Workbook by joining opportunities to transactions. The challenging part is matching opportunity items to the actual invoice lines if they differ.