Calculator, I should estimate about 1.5% in closing costs...but my closing costs and fees are significantly higher (double digits).

Expect an investor to want to get a double digit return - it’s rare they sell for face value just fyi

I’d also install security cameras and get a no trespass order so she doesn’t make her way back in through a window while it is vacant.  

NYC area is preferred, but NY is fine as well if they are digitally savvy - I.e.  

Double check either way.Also make sure to get the sewer inspected (camera).http://www.stlouisco.com/PropertyandRoads/NeighborhoodServices/WaterServiceLineRepair

It is probably worth giving DIY self-management services a shot -- aside from providing the basics (listing, tenant screening, digital lease creation, rent collection, and maintenance tracking) some services also offer your tenants additional capabilities which makes it an easier sell on your end when getting tenants onboard (ie. their ability to report on-time rent payments to the credit bureaus can act as a method by which you can incentivize them making all payments on time).  

If you use smart locks like August and a Ring security camera you can double check to make sure they showed up and left when they said they did.

This might not be a big deal when outdoor temperatures are in the upper 30's but when it drops down to the teens or single digits for extended periods of time it can be problematic.

Own 2-digits properties.  

We live in a digital age.