As a layman/laywoman, you wouldnt have any idea what makes a good real estate attorney versus a bad one, but your agent who probably works with dozens of them if not more does know the difference between a good one and bad one.

People were buying houses despite the negative cashflow betting that they'd sell eventually and make a ton of money on the appreciation regardless of the short term cash loss.  

You will need to determine if what your costs to do that are worth versus what you think you could get out of him.

One door versus 4 might be something to consider.

It's my turn to give him a smirk and ask when he'll pay off the bet.

Many of those that do have a college degree majored in an unrelated subject.You aren't the only one struggling with this, I'll bet 90% of the people on this site struggle with the same issues.I see you're in CA. 

But i think real estate is a safe bet until the next black swan event anyway.

If you are not a realtor, using Zillow or Yelp will be your best bet.

FYI, many lender's would view this transaction for hospitality financing versus apartment financing.  

I would think that assuming that it doesn't cost an arm and a leg to bring them up to code, that might be your best bet.