Finding durable products at reasonable costs. 

The challenge with unsafe areas is (1) potentially higher cost of maintenance such as broken windows, etc. and (2) this is by no means meant to be discriminatory but anecdotally from people I've spoken to the challenging tenants tend to be at the lower price points.

I would guess an older home might be more cost to insure?

I had a call with Simpletalk a few months ago and seemed pretty interesting but haven't pulled the trigger yet as it is costly.I know services do white labels and people brand it into their own AI call services, which mean a lot of these AI calls may actually be the same service...How much does Air AI cost?

They are far more common now and harder to find models without but:1) these add cost to the purchase price2) they don't bring a lot of value3) they can leak or detach and damage the propertyI own around 50 doors and I cap off the line at the wall or in the basement with a valve and a cap so the potential for leaks is 0.00001% :-) 

Here's an article with FAQs including the cost of a study.

You should only be liable for tax on any appreciation since you inherited the rental (minus the cost of your improvements). 

Rentrange costs the manager to run each report, so as long as you do not abuse it or send the PM 30 properties I would help you.

If I were to purchase an Airstream to use as lodging while I travel across the US to my rental properties, make repairs, and perform lease turnovers, would I be able to not only deduct fuel and campground costs but also depreciate the purchase price across 5 years? 

If you have a good FICO, a decent down payment and closing costs, go ahead an do the first one.