Going up ever since because of more people moving into real estate instead of other assets as a consequence of the crisis.But the rent hasn't increased proportionally, while taxes have.

You can also get an engineer or even a plumbing company to check the compaction and a perc test may indicate absobtion that in turn may indicate how compact the fill is.

Cities with a high proportion of steady jibs: government, education, and healthcare are usually good.

Do I allocate the credit proportionally to loan fees (amortize 5 years) and other closing costs/basis (amortize over 27.5 years) or can I select one or the other?

A normal market is when property values go up proportional to inflation.

So getting back to the OP's question, to best lower taxes on a potentially one-time windfall, the goal would be to acquire a business with a larger proportion of tax-advantaged assets like equipment over real property.  

We just have to keep accurate accounting of the proportions of all the payments, is that right?

The part of the cash/equity that is contributed by each person involved (bank, homeowner), is directly proportional to the size of their risk.Rental properties follow the same Risk Formula. 

How likely to help you avoid serious mistakes and the proportionally serious financial losses they tend to bring?

@Skip FriszMost of the mini splits (you can get them with a wall mounted head or with a compact air-handler).