A good attorney, RMLO, and servicing company play a big part of this. .

Same carpet in b+ area will get 10 years plus.i stand by my sustaining maintenance/cap ex estimate and hope my response indicates why.  

You’ll need to treat it like a business—handling tenant management, accounting, legal compliance, property maintenance, and more.That said, when done correctly, it’s a powerful tool for building wealth!

If you asked me to run a ton of properties, I would still be happy to do it, I may just charge a service fee at some point.

In terms of maintenance, they are generally safer because you are not responsible for the exterior and common areas and potential leaks, etc.

On average, you will spend 10% of your income on maintenance per year.

Quote from @Erick Pena: A "good" rental property is one that covers all expenses (mortgage, taxes, insurance, maintenance, property management fees, and any other costs) and still leave a surplus (commonly referred to as cash flow).Calculate cash flow as: Cash Flow = Rental Income − Operating Expenses − DebtThere's much more to it, but that's the basic idea.

JD, don’t disagree on some of the points you’re making above on responsive Web versus mobile app development, but it all comes down to level of engagement and what you’re looking to do with a site or service.

So no leasing agent, no maintenance. 

It isn't having paid off properties that offers security, there are still taxes, insurance, maintenance and management involved.