Kenny with regards to making sure that the tenants aren’t going to be negatively impacted by a recession or other economic hardship out of their control.  

I am not sure about 403(b) but 401(k) and 457(b) have the option to let you borrow money out of your account up to $50k or half of your vested account (which ever is less).You usually have a 5 years repayment plan (or sometime 10 years for some very narrow loan purposes).If a loan is offered by your custodian, usually you can get a check in a few days and they may charge a small administrative fee.The interest rate is usually a little bit above prime.The interest paid is going back to your retirement account.Now on the negative side:To get the loan out, you will have to sell some of your retirement asset to get liquidity.During the time of the loan, your retirement account will grow slower as there would be less money in it.If you separate from your employer you will have to repay the balance of the loan immediately.

However, I only recently finished "Rich Dad Poor Dad" and "The Book on Rental Property Investing" (thank you Brandon), so I now realize I've been something of a hobbyist, not the serious investor that I should have been trying to become.

It could negatively affect someone and their family in ways that you’ll never know.

The article says the fed are “willing” to go into the negative if necessary.

While I only browse the forums once every few weeks, I don't see very much discussion on industrial/metal building lease space.

It will lead you to overlook the negatives and make bad decisions. 

Hello negative interest rates?

I only work with investors.

The numbers are tight , the cash flow is negative the 1st year (not looking good) , also I didn't see the other 3k for the refi closing so all in all (6k in closing cost) with the market like it is you should be able to make/ find a better deal. a couple of options would be to do the work yourself and cut the cost of the 20k you have to put in it, move into it and pull 80% out that would give you 124k, negotiate the price lower .