Hi Todd,
Choosing areas to invest in are really going to depend on what your strategy is.
I personally like higher quality areas with higher likelihood of appreciation, but a little bit less cashflow. Therefore I invest in neighborhoods on the east side of the city (Evanston, Norwood, Madisonville, Pleasant Ridge, Deer Park, Madeira, Kenwood, etc) - my basic rule of thumb is to stay as close to Interstate I-71 as you can.
If you are okay with C,D class areas in exchange for higher cashflow there are neighborhoods on the west side of the city or further away from downtown that can accommdate this.
Downtown neighborhoods (Biz district, pendleton, OTR, Mt adams) are really going to be your higher end plays that can still cashflow enough to cover all of your expenses but CoC is going to be <5%. Downtown is more conducive for short term rentals in building that allow such.
Hope this helps! Reach out if you have any more specific questions.