Let me elaborate on some details about this so you'll be guided on what you can do, Tree.

You can use Google Maps to help you find the location of your customers or vendors when you're only using QuickBooks Desktop. Aside from that, you can send the address information to your mobile number, or save the location or direction information on your Google account. 

For now, the auto-suggest address feature for customers isn't an option in QuickBooks Online (QBO). As a workaround, you can copy the address from the Google map and then paste it when adding a customer in QBO. You can also add the addresses manually. 

Additionally, learn how you can manage customer profiles so you can add them to transactions or invoices. I've added this article for more information: Add And Manage Customers In QuickBooks Online.

You can always let us know if you have further questions when adding customer information. Getting you covered anytime is our only aim to assist you.