How to Evaluate a Neighborhood for Buy and Hold

[Leigh Ann Smith]

I have been using HAR to gather statistics on a couple of neighborhoods we're interested in. Does anyone know if there are any formulas out there that would help to determine whether a neighborhood is a good one in which to invest in rental properties?

Example - 2 adjacent subdivisions in which we are looking have a combined total of 2927 single family homes that are 35-50 years old. In the past 2 years, there have been 256 homes sold (8.7%). Currently, there are 56 homes on the market (1.9%) and exactly 1 home for lease. Median home price is $110,000. (This is in the Houston area.) Zillow ranks the high school as a 5 out of possible 10. Taxes are high (2.9%) and flood insurance MAY be needed. There are so few rentals that it isn't easy to find a good number, but they appear to rent for $1,100 - $1,300. 

Is the low number of rental homes is a good thing or a bad thing?  Does it indicate that investors aren't getting a good enough spread to make buy and holds feasible?  I would love to find some kind of "rule" to help us decide whether to focus on this area or to move on.