But, could I minimize risk of renter defaulting on payments for the 2nd property by turning this property into a section 8 housing unit with guaranteed income from the gov't?

There's also potential for developing "shared living" units where 2 or more people could share space, etc.

Within a year my wife and I acquired four multi-families properties with a total of 20 units, and eventually another building to rent out (currently a bait and tackle shop) as well as an Ice House.

I'm planning to use Brizo luxe gold fixtures in bathrooms. 

Building small units in low unit count is expensive.

The only way to do it with multifamily is to buy an uneven unit (one big and one small) and leave the small unit vacant for a year while "living" there.

I see from your intro that you are focusing on small multi-family 10-30 units.

The unit is a classic "attic apartment" and has sloped ceilings.

Some of my CA investor friends are doing value add, like ADUs, short term or midterm rentals, house hacking (buy a 2 to 4 unit for 5% down and rent out the other units or a SFH and rent out the rooms) here.

I only own one rental unit (this one) and don't accept people who have been evicted, but I would not accept someone in a current eviction proceeding either.