However, you are carrying multiple mortgages and there are certainly associated risks.

He was willing to carry back 18% on a 2.1 million 48 unit apartment building.

Alternative financing in this instance was getting the sellers to carry a mortgage. 

It's really the same thing as saying 25 year useful life, but doesn't carry the same subtext of - the building will be worthless in year 26..

If they fit the definition of a "real estate professional" not only is one allowed to deduct ALL expenses in the current year and will no longer have to carry over losses that exceed their income over the years as with passive income, but, if married and filing joint, they may even deduct their expenses against their spouse's income as well.

Why else carry on. 

To carry the analogy further, are the other patrons more or less likely to come back to this bar?

The ideal situation is to find sellers willing to carry back a note (10% to 30% @ 7% int only w/ balloon in 5 yrs).

Also, if all of your rentals use the same thing, you can carry less materials for things like repairs and touchups.One last thing, alot of the contractors can source items cheaper than Lowes/Homedepot at local supply houses.  

For all of 2015, however, the building remained vacant.I'm wondering if I can count the depreciation expenses from 2015 in that year, and if not, can they be carried over to 2016?