I would not purchase a 100 year old small multi with all of these issues when I could only expect a 13% ROI. 100 year old buildings that have been updated and don't have mold are very expensive to maintain.  

Overall, maintain control of your money no matter what through the process!

Anonymity usually refers to keeping your name as far from association with ownership as possible, while maintaining said ownership.

Aside from the resale consideration, what will the impact of the location be on maintaining high occupancy with good tenants?

Unless it is tenant caused damage it is your responsibility to maintain your property.

Do you charge for monitoring and maintaining vacant units?

If you own it, aren't you responsible for maintaining it?

Should there be a separate LLC to manage the rentals (lease, collect rents, fix and maintain, etc.)? 

It's an historic neighborhood originally constructed of primarily SFHs right in the center of a metro area in a beautifully maintained neighborhood.

It has been well-maintained overall, but has not been updated (knob and tube wiring, radiator heat, no central air, plaster walls).