I have come across an owner of a fairly large commercial building 16K sqft.

I am looking at my first "large" real estate investment.

It all depends on location and quality of the golf course.One of the great aspects of a golf course in terms of depreciation, is that a very large portion (sometimes up to 60-80%) is actually land improvements, which depreciate over 15 years as opposed to 39 years.

I have apartments with many large, old double hung windows around 28"x64" in size.

Last year in 2018, we did a large renovation on the property.

Like you I know many large apartment developers that are just quietly slipping elsewhere.

I have a lot of commercial truck experience, so I am pretty comfortable backing a large trailer into a tight space. 

Large companies would automate the BRRRR process and dominate.

That's pretty easy to do when your overall competition largely consists of people who have trouble understanding the long-term outcomes of the bad business decisions they make and execute.

Although it has strong cash flow, and secured equity, I still have a large balance on my HELOC.