I own multiple SFHs as rental property.  I purchased a 4k sqft investment home that is built perfectly for a multi home layout with some renovation.Must i have the home rezoned?  Or can i have 2 different power meters...

Instead of trying to actively manage investments in singles and doubles have you considered investing passively in syndications?

This is largely because I can typically get higher rents in B and A-class neighborhoods without relying on Section 8.I’d recommend focusing your search on C and C+ neighborhoods, for both multi-family and single-family homes with more than three bedrooms.

They are billed as "a scientific approach to single-family rentals" and use "institutional grade property management," which usually means they are a tech company in real estate and likely either don't have the existing property management relationships in each area or you chose an area where they don't have enough units through Roofstock for the PM they chose to care.

There is a neighborhood in Los Angeles where there are very old covenants that state you can only build a single story home.

It really sucks to kick out single moms who have not paid rent in 6 months when they are crying in court. 

Actually the IRS does not tell us what we can invest in, only what is disallowed (life insurance contracts and collectibles).Allowable investments for SDIRA investing include the following:Residential real estate, including: apartments, single family homes, and duplexesCommercial real estate Undeveloped or raw landREITs (Real Estate Investment Trusts)Real estate notes (mortgages and deeds of trusts)Promissory notes Private limited partnerships, limited liability companies, and C corporationsTax lien certificatesOil and gas investmentsPrivate stock offerings, private placementsJudgments/structured settlementsGold bullion Factoring investments

When tenant exited, the living room had a single broken horizontal blind and the right window broken. 

The indoor malls that simply offered shopping and a food court are the ones dying off.I've seen some malls be demolished and replaced with high-density single family developments. 

Once you are on site you can decide if your $20K should be used as a downpayment on a double to house hack (to stop renting), a single to just stop renting, or a single to lease out.