Thanks for posting! I'll do my best to answer your questions.
First off, regarding your multiple entity structure and the shared checking accounts. I've heard of all sorts of entity structures, however, you'll need to make sure --with your accounting and legal professionals -- that our structure is appropriate. One does not want to accidentally pierce the corporate veil.
Regarding how you use classes for each entity in the multiple entity structure -- great idea. Classes are a powerful tool you can use to cross cut into categories across all your accounts and transactions. I go into some detail in the ebook where you might want to use sub-classes for enhanced reporting. (In fact, subclasses sound like a perfect fit for your setup).
Also, because this guide was built from real world experiences, it will probably have a few unexpected landlord bookkeeping tips and tricks you will want to use. Even if you think you've got QuickBooks under control, after reading this you might wonder how you ever lived without some of the best practices I teach. I've included the table of contents below for your reference:
I hope this helps! Best of all, your purchase is risk-free: I guarantee your satisfaction 100% or only pay what it was worth to you.