What's the difference between sales by customer summary vs income by customer summary? Wondering if there is a difference? If it matters which one I view?

Thanks for checking in with us, ayushi.

Aside from the descriptions provided by my colleague on both reports, the Sales by Customer Summary report tells us what the total sales for each customer as well as the total sales for each job. While the Income by Customer Summary report shows us the gross profit from each customer. The gross profit for each customer is calculated as the total sales to a customer less the cost of goods sold to that particular customer. If you need to modify the reports, just follow the steps below:

1. Go to the Reports menu.
2. Find and open a report on the search field. 
3. Use the basic filters on the report to adjust things like the report dates.
4. Tap Customize.

Then, proceed to Step 2: Customize a report section in the Customize reports in QuickBooks Online (QBO) article to modify it. Visit our Reports page for more insights about running reports in QucikBooks. 

I'm just one post away if you need a hand with exporting your reports or nay QBO related. I'll be here to ensure your success. You have a good one.