all three are distinctly different in form and function.roofstock is more of a MLS type system highly automated representing civilian sellers by and large and some turn key companies will list their stock on Roofstock.. its pretty snazzy however after care is between you and the PM.Homeunion has some hybrid of turnkey marketing company in the same vane as Jason Hartman Maverick Norada etc.MI is what many consider the gold standard in turn key investing.. very deep experience in the space.. and control all aspects..

I would say you need to pay on a % scale with a base pay. 

What scares me is how large a mortgage or money borrowed is as compared to the rent you charge for a property.

Also, most sex offenders are one time offenders with no actual sexual attraction to children in general and these days a large number of sex offenders did not even offend a minor. 

I would say if dems take house and senate and negate the trump tax cuts that will have a very large negative impact on small businesses who are a big driver In the economy.No matter what, 2020ish timeframe expect a decline in home values and economy

For us to scale much bigger, one of us will have to quit our day job or we'll have to hire a management company.... we'll jump off that bridge when we come to it ;-)

Is the property zoned for a duplex, if not you will need a variance from city hall with is another headache.Also, you do not want to make tenants live thru a large renovation as you mentioned. 

The guys you see working on the large upright structures of steel at a petrochemical refinery. 

This way you can start taking advantage of economies of scale.

Try one thing and stick to it until you get what you want, then scale.