However, since parting ways with my partner, I'm striking out on my own and facing some challenges. 

If the thought of walking around the neighborhood at dusk strikes you as preposterous, you should not invest there. 

Ignore sob stories... or consider them as a strike against a person if they're trying to play on heartstrings to qualify.Congrats!!

This will ground the building from an electric strike.

This strikes me as a wholly ethical and legal arrangement.     

If the park is located in a larger metro area, they probably have connections with several banks and will save you a ton of time (and perhaps secure you better terms).If you pursue all these avenues and still strike out, then you have a compelling reason to go back to the seller and request he/she offer seller financing.

unfortunately there's probably not a lot that you legally can do here - hence the name Bandit...Maybe instead of declaring war, you could try to strike a deal with your competitor. 2 heads are better than 1, and there's always a synergy if the parties are willing to play.

I'm hoping to find an amazing four plex but so far I've been striking in Zillow/loopnet and similar sites.

Or maybe a professional looking typed letter on a letterhead would strike them better?

It's a good house, 12 years old, it strikes me as one of those rentals that could be held for a very long time.