For my day job I do financial modeling and consulting for billion dollar companies which has turned me into an excel ninja.

We tried to design it to fit well in the sweet little neighborhood and have the style of the old Ann Arbor homes, which sell like hotcakes, but the amenities of a newer house--mud room/first floor laundry, master suite with luxury bath, large kitchen, etc.

My wife and I plan on doing the same type of live in/flip/rent model that y'all did.  

NOW, if we are to have the HOA responsible for the interior of each of the units as well, here are the eminent problems I foresee:    - owners will be even more careless and act irresponsibly for their units since they don't pay for the repairs of the interior of their units    - because many of the owners rent their units (technically they sublease), they will be even less incentivized to maintain their units    - the HOA pays for all maintenance and repairs of units and owners get the benefit of rent    - repairs/maintenance of units is not properly proportioned to their respective owners, meaning that there is no incentive to keep my property up because any repairs will come out of the pocket of all other owners    - this penalizes good owners and rewards slummy owners    - this will put the owner residents at a big disadvantage because the owners who rent their units will cause maintenance fees to increase for all owners, especially due to high turnover    --> in Summary, this is a straight example of socialist-style system (I know, my family immigrated to the US from the USSR) and it will just sink our whole Co-op.  

@Major Thanks, I will at Old Louisville, and I am enamored with the shotgun style houses in Germantown and on Irish Hill.

The waters were already muddy.The current re-modelers policy is in the name of the LLC, not my personal name.  

This is a specific implementation of a 401k style employer retirement plan in an owner-only business, and is therefore much simpler to administer than a larger 401k that provides benefits to non-owner employees of a business.A self-directed Solo 401k is such a plan that can be invested in anything the IRS rules allow, as opposed to just what an institution offering the 401k is willing to sell.  

The style of room you are talking about is reminiscent of classic row house; railroad center room, windowless bathrooms (well, they mostly had windows, but it was really only for ventilation through the roof).If it is, depending on where the doors are sagging will tell you a lot about the condition of the bones of the house.

Just be cognizant that the 10-75 unit apartment space (pick your unit range) does not have a 3rd party management model that is dedicated to it in many markets.  

It is definitely a viable business model.