It really depends on what your goals with section 8 are. 

It depends on how much liquidity you have and how quickly you want to build up your portfolio.

(UNLESS OWNER OCCUPIED OR CAPITAL IMPROVEMENTS)If the land lord supplies heat, rent increase shall not exceed 4% otherwise don't exceed 3%.tenants 65 or older 2%new tenants increase can not exceed 5% over the last tenant's registered rentyou must provide a new tenant the previous rent amount in writing.you must apply to the city for each increase with 60 days notice, depending on the US department of housing and urban development for a unit of similar size.fines will be levied on a daily basis if in violation. 

It often depends on the definition of the zoning classifications within each city; based on the below info, I'm not sure which zoning classification a duplex would fall into.

The answer to this depends on the local market.

Really depends on how much you have in there.

Penalties:Misdemeanor of the first degree: This can result in a maximum imprisonment of one year and a fine of up to $1,000.Civil penalties: You may also face additional civil penalties depending on the specific circumstances.Permitting issues: Local permitting authorities might withhold final approval, revoke the permit, or pursue other actions against you, maybe not give you the CO. 

But really depends on your goals here.

Also would depend on foreclosure costs and time lines.

Lending - depends on if you are lending your funds or you are brokering the deal out.