In order to get a higher level of stability, at least starting out, I am looking in the B or C area.

My current effort level in real estate is not yielding the results I would expect. 

It depends on what your comfort level is working with tenants and how much money your working with to buy and rehab. 

(This is with Xcel Energy)

Most important thing you should look at with a rental property is your comfort level with the neighborhood & associated tenant base.

I also would note that the renovations completed upgrade the home: Recessed lighting, granite counter tops, new cabinets, new toilets for the entire house, new flooring for the whole main level. 

If you are planning on self-managing the properties, then I suggest starting with the 1-2 properties that are the "middle" level SFH or a small multi-family (duplex / triplex).

I see replacing the unit if energy conservation is important to you or you want a better functioning unit in your apartment for future use.

Consult with a professional who understands tax implications for foreign investors; In terms of US, few things to consider: since you will generate an active income - which is ordinary, you will need to choose entity that will save you taxes; consider how much income you expect to generate in a first few years; the state; for example with CA you have additional entity level taxes - for example tax on LLC starts at 800 per year even if you have no activity.

I believe Zillow has a county level Home Price Index.