I am by no means an expert as I am just starting out as well. However, I will do my best!
Assuming you did not include a PMI, would mean you are putting 20% ($20k) down correct? Does the property need rehab/renovation? Did not see that included as well. Also with the deferred maintenance, I am not sure what this is but would you be, after splitting it so say $5k best case including this in your loan? If so, that would lower your cash flow a tiny bit. But if it is coming out of pocket, that could be a cause for concern. Look more into your market rents. Check sites like rentometer, etc to get an idea. If you are planning on dealing with the property management, which being 4 hours away I would assume you are, give them a call as well. They should have a good idea of what the max rent should be.
I am in the same boat as you with the pre-1980 homes. They scare me! Even though they shouldn't. I am looking for advice myself with due diligence, so hopefully, someone can come in and help both of us there! I would not worry about the C grade neighborhood, although I would maybe check the crime rate there. To me, that is more important.
I would never trust the estimate values of these sites. They are simply there just as a way to keep you attracted to their site! They could get you in big trouble! I also do not think this is a good BRRRR property because you would be purchasing at $100k, assuming you fixed it up (which we don't know how much that would cost) and it was worth $125k. 70% of that ARV is $87,500. So that wouldn't make sense!
Hope this helps but maybe fill in some of the blanks and maybe someone else can chime in to help out!