Summarizing invoices totals by piano is easy!
FROM THE WEB APP
Step 1: Click to Open/Create a new invoice.
Step 2: Check the "Summarize amounts per piano" box.
Step 3: Done
FROM THE MOBILE APP
Step 1: Tap to edit an invoice.
Step 2: Click the "Show More" button below the Invoice Details section
Step 3: Select 'Summarize amounts per piano'
Step 4: Save