Re: Retirement
Sorry cant help you with the US perspective , since I am UK based but I can suggest that going the property route isnt your only option. If you place so much importance to teaching , why not become a private tutor? Work towards that goal as a side income.
You see, retirement may mean total goodbye to work life for many , but than again, for many others retirement only means goodbye to a full time employment and they still have to work on and off for smaller periods of time on smaller income . In essence they dont account for a stable income or a job.
In my opinion, when one has nothing to do , life can become really boring and only gives more space to illnesses. So keep yourself busy with your other skills that you never got time to enhance through your life .