Can I easily archive all my data after I eventually close my business and leave QB? And access it on my hard drive for tax/other purposes?

Export all of reports out for your archive. As for insurance, convert your data to QB Desktop file. You may open it later on the trial license of QBD. 

Thanks! But, just to be clear ... one day I will leave QB totally and not expect (to or wish to) rely on a continuing licence - will I be able to access my archived data licence-free?

Thank you for getting back to us here on the Community page, @DavidB3.

Allow me to share additional information about archiving data on a close QuickBooks Online (QBO) account.

Once you decide to cancel or close your account, you have read-only access to your data for a year after the cancellation date. That said, you need to export your data to Excel within this period so you can have a copy of them for future use. Opening/saving your file on a hard drive is currently unavailable. If you wish to prepare your forms or taxes, you need to resubscribe for the month so QuickBooks will download the latest tax forms.

To export your reports to Excel, click on the Export to Excel button from the Export icon from the Report's page.

Also, check out the details from these links to learn more about canceling QBO subscription:

• What happens to my QuickBooks Online data after I cancel?
• Cancel your QuickBooks Online subscription or trial

Post again if you have any other questions, @DavidB3. I'm a few clicks away to help. Have a good day!