Based on what you listed, you have calculated the cap rate correctly at 8.36%.

If they're market rate units - only pull comps from market rate properties.

For Detroit properties specifically, the city assessor is aware that Detroit has the highest millage rates for rental properties in the state.

The interest rate is at 3% on the home and doing a cash out refi would eliminate that low interest rate.

You'll see the spreads trade unwind as rates lower(mega cap sell, small cap buy). 

Here's a bit more in detail about how rates are calculated for DSCR loans:1.

Quote from @Yoni Meth: Hey All,I’m currently investing in Columbus, OH, and generally happy with the market, but I’m looking to expand into another area where single-family home prices are more in the $100–$150K range.My criteria:Strong cash-flow potential (ideally close to the 1% rule).Reasonable appreciation upside.Population growth and a diverse job market.Normal/Reasonable property tax rates (nothing extremely high that kills cash flow)Neighborhoods with acceptable crime levels, preferably C and above, avoiding high-risk “D” areasIf anyone has experience in markets that fit this profile, or recommendations for cities/markets worth exploring, I’d appreciate your insights.Thanks!

• And what lender terms make the biggest difference (interest rate, LTV, DSCR, etc.)?

Your talking about a 50yr and it's what, maybe 7, 7.5% interest rate.

You could bring less down and possibly have a lower interest rate since you will be living there.