And since he can pick and choose his tenant in the other units. he will mitigate those issues as well.

And he bought in all the top cash flow markets but bought 30k and under deals and well not to beat a dead horse but I have spent 3 years helping him to mitigate his loss's and even I can't do that and I have owned well over 350 rentals in the cash flow markets.

-Use licensed contractors (especially for things like electrical work)-Limit tenant access to dangerous spaces such as the attic. 

So, for example, if you personally had knowledge of a loose step in one of your properties and didn't fix it and then your tenant was injured on it, even though the property is held in the LLC, since you had actual notice of the dangerous condition you could still be held personally liable for the tenant's injury.

Completely legal, as long as it's documented and applied equally.Some Property Managers charge tenants a "risk mitigation" fee that is based on credit score.

I would like to know, what are the dangers of buying a home that was built that old.

A good CPA that specializes in real estate & leverages sophisticated tax software (not just some H&R block or Turbotax person) will help guide you to maximize your after-tax wealth and mitigate audit risk.

Frequently, if a tenant wants to move midway through a year lease, you as the landlord will be compelled by the court with a "duty to mitigate" so very seldom are the tenants locked in. 

Here's why:Let's say I sign a tenant to a one-year lease, and 3 months in, their personal/professional situation changes, and they break their lease and move out after a 30-day notice (or maybe less).I am required, by law in most areas, to "mitigate my loss" by remarketing the unit, making it rent-ready, and starting up my lead generation machine to get applicants, funnel them into my screening system, identifying good candidates and ultimately leasing them up.

I would not invest in any city on Neighborhood Scouts’ list of the 100 most dangerous US cities.Metro area population greater than 1 million.