If your problems were really caused by an unexpected ac failure (can’t believe your realtor didn’t get seller to throw in a home warranty.) and not lifestyle.

After I placed the 5 day notice on her front door, she text me the next and said she would pay the full amount so I told her to go to the bank and deposit it and she did so we are back in business.

Are all Daikin units prone to failure?

I am not sure what type of real estate investing you're considering, but it sounds like, with your family and busy job, you won't have a lot of time to be hands-on or personally involved. 

Still, my soft heart left my head feeling pretty rough, like a "failure".I don't think with your experience and 17(!)

A third reason people are selling is failure to run their business and their finances on a fiscal year.

As a landlord, you are representing yourself to the public as a business. 

A good landlord wants to do reasonable business to have continued tenants.

Quote from @Benjamin Finney: I'm curious what real estate investors and private money lenders like myself use to inform their businesses strategy and predict future market conditions.

I’m an out-of-state investor working on building my online presence, and I’m currently running into an issue with setting up my Google My Business (GMB) account.