3) Are there any other big concerns that I may not have mentioned?

With parking and set backs and the size you mentioned I would be surprised if you could get a 4-plex on it.

As Wayne mentioned, time is of the essence since this is a distressed sale with an upcoming sale date.

2) You mentioned the property is old ... could it be eligible for historic tax credits?

This means having systems in place as I age so that I am not the only cog in the machine. 

Like @Gene Hacker mentioned, many of the properties in those areas are in bad shape and bad neighborhoods.

No, with truly self-directed Solo 401k plan you can contribute first $18,500 (plus $6,000 catch up if you are over 50 years of age) up to 100% of your self-employment compensation, then on top of that you can do additional 20% of your net SE income (25% if you are incorporated) for combined maximum of $55,000 ($61,000 for those over 50).

For example, if you mention money, or paying someone for something, maybe they consider that a marketplace discussion instead of a request for assistance.

Somebody mentioned on another thread and I loved their examples: "promptly" is general, "within 24 hours" is specific.If that's not your style, then consider hiring a new manager.  

We go really cheap on some things, like paint,  towel/toilet paper holders, and go higher end on things like faucets.. as others have mentioned, it's an art and you have to find your balance.Also... so  many people forget-- this is someone's future home, this isn't a mutual fund/stock, so you need to focus on what things will make your tenants happy!