As animal proof as it can be (yard also) and monitor closely.

I own a pool at my house and once a pool water gets out of wack it can take multiple days to get it clear again.The 2x per week price seems pretty reasonable for that peace of mind.I bought a gizmo that will constantly monitor pool chemistry and send me alerts if things get out of whack.

In the majority of cases, hiring a good PM will bring as good a return or better because they know the market better, can demand higher prices, can reduce losses through active monitoring and swift action, reduced turnover time thanks to their network of vendors, etc.

My girlfriend is so bogged down with three software programs that cannot talk with the Oracle program that she has to use three monitors and try to do work on one and then figure a way to transfer that data to the next monitor with the next program to end up on the third monitor with the third program and hope that the numbers end up in the right places and have the same totals.

You're the landlord - not playground monitor. 

If you're looking for appreciation, the two strongest influences on demand (and appreciation) are population and job growth, so monitor those.If you're looking at which markets are volatile, that is impacted by many variables... population growth, job growth, job/industry diversity, local politics/regulation, development etc...Example: San Antonio's economy and job market is really driven mostly by health care and aerospace. 

@Will Fraser Thanks so much for your comprehensive and thoughtful response.I absolutely agree that every economic situation is different depending on what triggered the downturn, so I am continuing to watch and monitor how things progress in this current, ever-changing environment. 

They usually have some good locals that monitor each state forum. 

Our reservations dept monitor each reservation to make sure it is signed. 

I suspect most of my tenants don't monitor their credit and haven't noticed the improvement.