I agree with @Chris Seveney that Del Ray would be an excellent place to do this.

Deal acquisition is an art, so dig in and make sure the deal is good and make sure the numbers at up to what you think is good! 

I’m not sure which one is the most realistic.BP Rental Property Calculator Rental Calculator: https://www.calculator.net/rental-property-calculator.htmlWealth Optimizer: https://www.rpmengage.com/wealth-optimizer Zillow: https://www.zillow.com/rental-manager/resources/rental-prope...In addition to the ones listed above, I’ve also downloaded Excel spreadsheets from a couple of other sources.

Where to buy in Detroit is just as much art as science.

However, I would write down in an excel sheet all of them and process that go into a rehab and do a estimation column and write-down those numbers. 

A more holistic approach that is more art (experience, knowledge, and feel) than science (spreadsheets), but it comes with time.

and it's not that anywhere is "saturated," it's that prices AND rates are high.or as @Travis Timmons said - a creative niche that you excel in will cashflow. 

An activity is a personal service activity if it involves the performance of personal services in the fields of health (including veterinary services), law, engineering, architecture, accounting, actuarial science, performing arts, consulting, or any other trade or business in which capital isn’t a material income-producing factor.7.

There may be some excellent opportunities there.

That being said, if you’re exploring the BRRRR method, a DSCR loan could be an excellent fit for your goals.