Have you thought about pending regulations in those areas? 

In most municipalities approvals have a few year shelf life and in the event new regulations or new zoning bills are passed you could lose the benefit of the in place zoning/development procedures.

Very few lenders do well in the space due to the risks involved (novelty, rules/regulations, etc...). 

Here are the 7 material participation tests as outlined in the IRS regulations:1. 500-Hour Test: The individual participates in the activity for more than 500 hours during the tax year.2.

there are numerous recent threads on BP by folks who bought something because it looked nice, or an agent recommended it, and they didn't see it themselves and approach it with any skepticism. 

In my case I operate using a Regulation D 506c and 506b, and operate a personally guaranteed debt fund. 

I am agnostic on geography other than looking to stay East of the Mississippi and out high tax/high regulation states. 

Search the BP for ADU appraisals to encounter numerous examples.

However, there are numerous ways to CREATE investments that have 15% or more cash flow AFTER repairs and allowance for cap ex.  

In general you should start looking for a single family house that has zoning regulations that allows to ADU (Accessory Dwelling Unit) or can be setup to house hack.