And given that it is determined by the market (at that point in time) and unchangeable by you, the only remaining factor in the formula to determine property value is the NOI.

But you absolutely cannot tell me that the entire world will change around you, and RE investing will go on completely unchanged because of the "personal touch" aspect.  

Psychologically, the seller gave you a bit of a feeling of ownership(after which you now have some fear of loss,) and when people own things, they tend to place a higher value on those things prior to taking ownership.Why not try this- estimate the annual cash yield on your initial investment(under the theory that the units were all like the initial 3 units,) then adjust your offer downwards such that your percent yield on capital and time invested is unchanged?

In my market most of our agents require buyers to use the MLS contract, which, if unchanged, do not allow the contract to be assigned.  

If the article is saying "residents want capital improvements and offer to pay higher rent to justify them" that would be fine, but I'm sure the point here is that they want the owner to spend hundreds of thousands of dollars yet the leave the rent unchanged. 

This system is elected if someone wants to slow down depreciation or sometimes is mandatory. 2) GDS - it is unchanged as @Eamonn McElroy mentioned. 27.5 for residential and 39 for nonresidential. 

Lowe Mill is a transitional area - could be a home run with appreciation, or could be unchanged in 10 years. 

All you can do is get somebody in trouble but your scenario will be unchanged.

Your net worth is exactly unchanged, you've just liquidated a portion of it.

I wouldn't recommend amending prior tax returns, namely because the tax implications will be unchanged.