The type of investing he supports in long term investing to secure your retirement...NOT to improve your current wealth.

I did use it for a rental for a while, as the market improved.

Eventually through all the improvements the all in budget was 240k, which was still great.

Here's what he's referencing is my guess: In the TCJA lease hold improvement property was incorrectly written in as 39 year...when really it's 15. 

Are you providing a Tenant Improvement (TI) allowance to the tenant?  

@Darrell Wallace, this article in Accounting Today references "Correcting an error in the Tax Cuts and Jobs Act that prevented qualified improvement property from qualifying for 100 percent bonus depreciation."

Now I'm reviewing to improve my system to determine if and when an appraisal is appropriate. 

For commercial properties, I advice my clients to focus on the business plan and yield (IRR) as Cap Rate is only a point in time measure and may not tell you the potential for improving the value. 

So, if you are buying correctly, DTI improves with every purchase.3) Get educated. 

This makes them even less likely to improve their lives and creates a more dependent society which means bailouts will have to be bigger the next time.