wooden_flower Volunteer Community Mentor.
Unfortunately, the data history reports do not include sales tax (unless they have changed recently). So I do not think there is a report that will show you the total with tax.
You could request the history report, copy it into a spreadsheet, then manually add the purchase total in a new column. From that you should be able to calculate the tax paid. Or your credit card issuer may a report you can run for a specific vendor, so you could get your total spent with eBay that way.
To request the history report, go to account settings >> request your eBay data.
