If a parcel was owned by a company that manufactured anything, especially metal things or used chemicals, you can bet there is some level of contamination. 

They did do some large cap ex repairs like all metal roofs and burying the power lines but they didn’t do anything to bring people in like building a nice website. 

However, there are still places that need to have the pipes replaced still which means they do not have clean water yet.When buying a house in Flint the buyer need to have a home inspection done as well as a water test done (there are plenty of certified testing companies that are under $150) to test for heavy metals in the water.

I'm not too concerned about the structural integrity as the two that see water are 20 year old metal buildings and the flooding is minimal intrusion.

I can't speak on how demo is done in certain states but from what I could tell you being a license contractor here in NY and you being in NJ which should not be much difference is do the following steps.1- have them demo and take everything plumbing and electric.2- the only scrap metal you should keep is copper, but also negotiate with the demo grew to reduce some cost if they want the copper, all other scrap metals are not word it.3- has for the electric, just have them leave you 2 plugs because that's all you need until you update all your electrical. mostly all power tools are cordless so I doubt you will blow a fuse and you don't need any light because you work will be done during the day.ALSO NOTE: do not have anybody mess/touch/remove with any electrical panel or any electrical box, leave that for a license electrician to do because thats a big safety issue that could bring a lawsuit if a non-license electrician gets any injury for attempting to do so.

Also, this house had a huge metal roof.  

Following are the similarities and differences between the solo 401k and the self-directed IRA.The Self-Directed IRA and Solo 401k Similarities Both were created by congress for individuals to save for retirement;Both may be invested in alternative investments such as real estate, precious metals tax liens, promissory notes, private company shares, and stocks and mutual funds, to name a few;Both allow for Roth contributions;Both are subject to prohibited transaction rules;Both are subject to federal taxes at time of distribution;Both allow for checkbook control for placing alternative investments;Both may be invested in annuities;Both are protected from creditors;Both allow for nondeductible contributions; andBoth are prohibited from investing in assets listed under I.R.C. 408(m).The Self-Directed IRA and Solo 401k DifferencesIn order to open a solo 401k, self-employment, whether on a part-time or full-time basis, is required;To open a self-directed IRA, self-employment income is not required;In order to gain IRA checkbook control over the self-directed IRA funds, a limited liability company (IRA LLC) must be utilized;The solo 401k allows for checkbook control from the onset;The solo 401k allows for personal loan known as a solo 401k loan;It is prohibited to borrow from your IRA;The Solo 401k may be invested in life insurance;The self-directed IRA may not be invested in life insurance;The solo 401k allow for high contribution amounts (for 2016; the solo 401k contribution limit is $53,000, whereas the self-directed IRA contribution limit is $5,500);The solo 401k business owner can serve as trustee of the solo 401k;The self-directed IRA participant/owner may not serve as trustee or custodian of her IRA; instead, a trust company or bank institution is required;When distributions commence from the solo 401k a mandatory 20% of federal taxes must be withheld from each distribution and submitted electronically to the IRS by the 15th of the month following the date of each distribution;Rollovers and/or transfers from IRAs or qualified plans (e.g., former employer 401k) to a solo 401k are not reported on Form 5498, but rather on Form 5500-EZ, but only if the air market value of the solo 401k exceeds $250K as of the end of the plan year (generally 12/31);When funds are rolled over or transferred from an IRA or 401k to a self-directed IRA, the amount deposited into the self-directed IRA is reported on Form 5498 by the receiving self-directed IRA custodian by May of the year following the rollover/transfer.Rollovers (provided the 60 day rollover window is satisfied) from an IRA to a Solo 401k or self-directed IRA are reported on lines 15a and 15b of Form 1040;Pre-tax IRA contributions on reported on line 32 of Form 1040;Pre-tax solo 401k contributions are reported on line 28 of Form 1040;Roth solo 401k funds are subject to RMDs;A Roth 401k may be transferred to a Roth IRA (Note that from a planning perspective, it may be advantageous to transfer Roth Solo 401k funds to a Roth IRA before turning age 70 ½ in order to escape the Roth RMD requirement applicable to Roth 401k contributions including Roth Solo 401k contributions and earnings.)

Here's an example that is contempo, clean, simple, metal with wood (for continuity to the floor), and it mounts in the same way as your existing balustrade:https://www.hubush.com/modern-stair-railing-ideas/...The hanging fixture examples might be a bit ornate for your architecture.

Car parts , motors , fenders , bicycles , all junk , but its all metal .  

But my lack of long term market understanding lead to over extension on my personal buy-and-hold properties. 2008 destroyed me as 95% of my tenants decided they no longer needed to pay... and some even decided that they were entitled to my mechanical systems and metal materials like plumbing and wiring... one even burned down a multi-family building.