The metal building erector I used to do some of the work wanted to lease the building immediately once his work was completed.

So 3 of the homes are metal/metal (siding & roof) and the the '91 is shingle vinyl?

You want something with some kind of siding: metal, aluminum, vinyl, or brick.

Few Notable expansions to mention are- Metal Works of High Point, BakeMark, Brown Truck Brewery, Future Foam, Glocal Leather, Lowes Cos, and Pennybryn coming in with a $35 Million investment as well.

It will have a 12/12 metal roof and a combination design of Hardy Board cemititous exterior paneling.

They tend to build a veneer front and sheet metal sides and back and be off the beaten path a little bit because they do not want to pay per sq ft corner money.Having said that there are generally more buyers because they are cheaper to purchase. if  a Dollar Store goes dark the second generational tenant pays less for a sub-prime location.

With a self directed plan, you can invest in a whole range of other things as allowed by the tax code, including real estate, mortgages, private company stock, precious metals, etc.In your situation, the idea of being able to potentially shelter more income from taxes (or make higher Roth contributions), and to be able to invest part of your portfolio in what you know would seem to be beneficial.  

@Ben SmithSelf-directed IRAs are ideal for diversifying outside of the stock market as they can be invested in alternative investments such as real estate, notes, tax liens and metals, to name a few.

(which reminds me that a voicemail today informed me my roofing metal is ready to pick up) So yes, we're guilty of working "in" the business instead of "on" the business but we do all that too as we self manage, do our own taxes and whatnot.

The windows and doors (including the garage door) are metal so little maintenance is required.