Try explaining that to the IRS.Schwab will not open a trading account for your IRA-owned LLC, nor will most of the mainstream brokerages.  

I'm not in an area where lots of 70k sq ft industrial properties trade hands all that often, but there's lots of smaller industrial properties.

If you trade into a more valuable property, as you did here, the increase in value is added to your old basis.  

It's also quite a bit more complicated than "this qualifies for 5 year and this doesn't qualify" since there isn't really a "list of every possible asset and it's depreciation life" most assets that qualify for 5 year fall under asset class 57.0 assets used in distributive trades and services.

All the trade websites say that in the end they're only a tiny percentage more expensive than regular concrete block because the labor costs go way down.    

This is sufficient size to have reliable trades-folks do good work at reasonable costs.

When trying to forecast the value of the property after the work is done, what tools/framework do you use?

In used to finance the international trade in my previous career and I understand that claiming that Panama City will become another Hong Kong or Singapore and that therefore Panama City's real estate prices should catch up to those of Hong Kong or Singapore.

@Eamonn McElroy with all respect, your answer confuses me further. its either passive or not.If its not, its trade or business income.   

Ask me how I know.....Painting is the single trade that everyone takes for granted - that is the hardest to do right.