What materials were used in building it and renovating it?  

It seems low enough that clients wouldn't balk and enough to cover the inflation-driven increases.  

It depends on the level of improvement, labor costs, materials costs, time costs, carrying costs, property tax, insurance, and on and on.A refi has loan origination costs, appraisal, prepaids, escrow, title, recording etc.

The report also noted "The analytical lab did note that in the bedroom, a large amount of particulate material was in the air.

@DA NguyenGenerally acquisition interest of a passthrough entity in which you do not materially participate is an above the line deduction that is also passive in nature.The debt proceeds need to be traced to figure out exact treatment of interest paid during the year.Consult your tax advisor.

Your typically installer will charge you $45 per stair in labor to install laminate or wood, plus increased cost of materials for stairnoses and such. 

The house has been rehabbed throughout the years, so the materials used could be anywhere within the last 100 years.Any idea how likely we may have walls with asbestos? 

Consider that one's win or lose is completely driven by the tax rate at contribution vs distribution.

In my area, construction sites are always left wide open with tools and materials everywhere.

The treatment is driven by fact and circumstance analysis, not choice, and quantitatively Schedule C is disadvantageous.