Another useful feature is enabling online payments, which makes it easier for customers to pay and can speed up the process.

Check out other online guides available here: https://www.biggerpockets.com/guides3.

At least that's the practical approach.  

You have a de minimis exception which is set at $2,500, and it can be doubled to $5,000 if you follow certain strict and tedious accounting practices known as AFS.

Your advice sounds practical, but it's really not. 

As you can imagine, we already have an attorney who specializes in real estate and an accountant who is well-versed in rental property accounting best practices (but she admits she doesn't have a lot of experience on the private lending side of the business). 

They have a great online portal for tenants and owners.

Out-of-state investors, do you recommend a reputable online source that provides crime rates and other demographic information of cities/zipcodes?

You: "No, but I want to play for the NBA some day, and I'll need a basketball court I can practice on for hours without interruption."

I would educate the tenants on why certain practices of the unit might cause it to break.