Quote from @Daniel Mendez: My policy is to set standards and apply them equally to everyone.

the more hands-on you personally are, and the more niche / creative / difficult the strategy is, the more the potential to cash flow (but also higher risk.)standard, professionally managed, vanilla LTRs in good neighborhoods basically don't cash flow right now with interest rates where they are.

In the event that you do have a true squatter its a fairly standard eviction process which is unfortunate but does happen in this business.On a preventative note if you have a vacant unit you can put in a security system that uses cellular and you will get notification if anyone comes in. 

Is it possible to find a single-family house for around 100k that is compatible with Section 8 standards? 

While commissions are negotiable, industry standard today is 6% of the gross base rents for the first 5 years of a lease term and 3% for any years after that split 50/50 between the landlord's broker and the tenant's broker.

Concept2 seems to be 'gold standard' out there.

Yes and all the lawyers will collect their standard fees. 

The loan caps vary across lenders, across experience buckets, across asset valuations but 70% - 75% is standard.9mo note at 12.99 i/o - Most say "12" months and then bake in a fee if it goes longer than 9 months.  12.99 is high. 

Unfortunately, many owners & PMCs maintain Class C & D properties to Class A & B standards. 

With standard ceilings, and single-story I would expect to spend about $100k for basic turnkey on that addition with a hungry builder.