My personal feeling is that "urban sprawl" in Cinicinnati has made Mason/West Chester/Liberty township quite the hot spots.  

I have heard of some hot spots in certain areas in Texas that may be worth checking into.    

I would say these area is the classic hotspot that doesn't fluctuate much because of tech economy.however if the O/P wants to invest in silicon valley area....I would say back in the 90s, "most" techie able to afford home in area like mountain view, palo alto.

I was wondering if anyone has a map of their local market highlighting the hot spot and the areas to avoid.

There are good rentals all over, not just in the hotspots like Memphis and PA.

@Michael Glaser If you are in a college town that has football & basketball you can become an Airbnb hotspot.

WiFi thermostats are great for short term rentals (AirBnB, VRBO, etc) as well as if you are in between leases or while listing a flip for sale.While I have not tired this, can it connect to a Wifi/4G hotspot?

That is a hot spot now.

Quick Tip: Kettering seems to be a hot spot for buy and hold investors - definitely a working class area.Cary

There's a company in Fredericton, NB (HotSpot) which has been handling parking - both private and public - for 3-4 years now.