Problem with this, is that not all sellers will be comfortable with this type of contingency or a contingency like this will render you uncompetitive.3.) 

Any service rendered makes the exchange ethical.

Landlords have a tendency to edit their own leases and you want to avoid any illegal clauses that could render your lease less enforceable.

Some are of the view that only the LLC should be named as the insured in order to maintain protection rendered by the entity.  

In what world would you see that as a suitable return in exchange for your risk of offering 80% + leverage on something based on someone's W2 income coming from a job likely to be rendered obsolete at some point. 

A couple highlights:MFHs can usually render better more cash flow since they typically cost less per unit compared to a SFH.MFHs can save you on capital expenditures since the roof, foundation, and other components are often shared.However, MFHs tend to see a higher turnover, I remember always feeling unsettled staying in a multi-family, but some people live in them for years.MFHs are often hard to value since they vary greatly in type and location.

The framing around both garage doors has been eaten so bad that the tracks for the doors have dislodged rendering the doors ineffective.

High taxes can kill cashflow, therefore rendering a deal no deal at all!

There are no zoning laws there, which is all well and good until your neighbor opens a night club that plays loud music until 4am, or turns their property into a pig farm or a trash dump or a brothel, or you name it, which lowers your property's value and renders it impossible to sell, and there's nothing that you can do it about. 

If the system is looking at the same 100 properties as comps for both myself and the housing authority, my estimate might be based on the average for some or all of those properties, without regards to any amenities, but the housing authority's estimate is going to extract a narrower set of values, rendering a far more accurate estimate.