More of a general trend, when we started we asked the same question. how low can I get it?

It is still a low income area that is up and coming and is becoming more desirable for it's proximity to the aforementioned areas.  

I went low end of middle.

Super low vacancy rates in SD, even STR's. 

It has shown nice equity growth although the cash flow is relatively low.

They use leverage in some of their funds, which can increase returns, especially if they have a low cost of capital (but potentially increase risk and trigger UBIT issues).

The owner occupant rate is super low compared to many states but as a rental it goes up alot.  

While I know that return goals are different for each investor and their specific goals, it seems that a bad or low-performing deal for one person might be what another investor is looking for. 

Population growth creates increased demand for housing, pushing rents higher.Rapid and Sustained Appreciation: In cities with abundant, low-cost land, new construction is often preferred over existing properties, limiting appreciation potential.

Unless you bought in D class, very low appreciation area, you should be sitting pretty.