I've been speaking with my CPA (who obviously isn't a lawyer) & my compliance coach from the business who set up my first LLC. 

They are two entirely different skill sets.

I have set up a Single member LLC for him, and am wondering if I should put him on payroll with his other employee(s), what would be the best thing to do as far as taxes and accounting go?

Set goals to go out and view houses, even open houses.  

Usually these issues can be solved with good communication and good boundary setting (if not, you need to think about getting rid of the tenant).

or we set up one from a small scale. 

Take that rate, set your formula and drop in your purchase price for every property you analyze, quick and easy and no need to guess or rely on unreliable numbers.

The listed price is simply a price set by the listing agent and owner.  

The option of flipping the SFH to buy a MFH might be a set back indeed.

@Tarik Nabi I agree that this in this case it is the landlord's responsibility to seal up holes and set traps.