Most folks bringing this up happen to have land available they'd like to utilize. 

And pick an accent color for the front door.

Did they leave owing a balance for rent, utilities, or other charges? 

Base on your calculation, $6K x12 = $72K/YR, then minus 12K/Yr(Tax, Ins, Mx) = $60K/yr then divided $783K, looking at cap rate (NOI) 7.6% which is high compare to the bay area cap rate.Usually high cap rate (8-12%) = high turn over tenants (Crappy tenants) lower appreciation.Lower cap rate (3.5 - 4%) = Quality tenants and high appreciation.Been an investor in/out of CA for the past 10 years, I will always pick bay area.GOOD LUCK!

TO MANAGE THE UNITS BY TAKING CARE OF TENANT PROBLEMS, REPAIRS AND TO PICK UP RENTS HE IS IN HIS 80'S NOW AND SAYS IT IS TOO MUCH OF A HASSLE FOR HIM NOW BUT NEEDS THE INCOME 

First, realize that at 95% of the current value of your home, if you've fully utilized your HELOC funds, you now have only 5% equity in your home. 

One of the first books i picked up for recreational reading was Rich Dad Poor Dad and i knew then that i was going to eventually get into real estate investing.

In 2018 I look to utilize 203k's to purchase duplex, triplex or fourplex fixers and house hack, particularly in the Oakland market. 

Utility costs?

Looking at picking up a duplex for 15k, needs 30k rehab.