If cash flow is your main driver, not sure how well the Madison, WI market would stack up. 

Like i got a recip to Mississippi for my CA / OR Brokers licenses and it was a whopping 13 question test I never figured out how they came up with thirteen questions its was almost like for me taking a drivers license test took me 5 minutes..

2) What percentage is their track record of delivering what they promise to deliver?

Specifically:The $100K limit makes no sense, unless she has a process and data showing the sub 100k properties have been the best investments in that market.Section 8 is problematic.Over the past 16+ years, we've delivered more than 550 investment properties and provide comprehensive services.

It’s about more than short-term gains; it’s about creating a self-sustaining system that prevents the very liquidation events that drive rents up and communities out.4.

A broker who can also deliver a reputable management company (themselves or an independent company) willing to take over management at closing is a real plus for any residential rental investment. 

How are they delivered?

. —- Again I’m not saying you have to do these things; it all depends what type of investor you are and what you are looking for however it is important to understand that if you shift the responsibility of either identifying the invest property or managing or any other aspect there WILL be a trade off — in this case the turnkey company has delivered on your goal of 8-9% ROI (projected... so TBC) and in return you have traded some of the other benefits of investing in RE for the convenience of not having to do much more than to look over the properties they have sent you and funding it from the comfort of your home, office, etc. ... again if this is the goal then you are on point but if the goal is to also partake in ALL of the other benefits of RE then you should understand that and not be surprised that it’s not a ‘stellar’ investment that checks all the boxes.

How about the simple obvious that the inputs to deliver the service/product have a base-line and market prices have, OBVIOUSLY, been at about as lean of operating profit margins as can be. 

Yes, check w attny as per @Ben Trageser.Also, see if you can negotiate with the seller to get the illegal unit delivered vacant on closing.