Is investing in a "rougher" area always a bad thing?

[Nataniel A.]

21 Unit building in San bernardino

1,495,000 asking price

Actual GRM of 8.8 - Market GRM of 7.6

It nets a little over 100K. 

From some research and asking around I've found that this specific area isn't too safe or somewhere you'd want to spend too much time in. 

My question: If I have a great live in manager, does it matter that it's not in the best area? I imagine I'd be able to communicate with him/her for most of the issues. If the numbers are good, vacancies low, and the checks are coming in why be deterred by a "rougher" area? 

Thanks!