What does "tracked classes and locations" mean? Does that mean I could i.d. expenses for Home location, and keep that separate from expenses for my vacation home?

Yes, cglaser.

The Class tracking feature is used to categorize your transactions. While Location is used to categorize different parts of your company.

This feature lets you track your income and expenses. You can use both of them together.

Here are my examples of expenses at home:

Location: Home 

Classes: Vacation Expenses, School Fees, Grocery, Utilities

You can read more information about this feature in this link: Using Classes and Locations in QuickBooks Online.

I'm a post away if you need anything moving forward. Have a good one.