We plan on buying 20 units over the next five years  

The seller hopes the buyer (gets pregnant) on the deal with tens of thousands of dollars spent or more and also if they have a 1031 exchange they can now be stuck with the choice or face a big tax penalty.If a seller does not have a full file ready to go the minute they go under contract then either the seller, the listing broker, or both are incompetent or they are trying to hide something  and commit unfair dealings by pulling one over on a buyer.

The termination of utilities could give you reasonable belief that she’s abandoned the property, but you’d still need rent to be overdue by 14 days and to serve a Notice of Belief of Abandonment. 

Although I do not know your area, thus I cannot point you to the best areas to look for these properties in, I can tell you one universal thing I have learned since restarting my Property Investing, and that is there are a heck of a lot of people within 30 minutes from where you live now that can help you. 

I don't want her changing her mind at the last minute causing me to turn away a qualified new tenant.  

Also a 10-minute walk to Harvard.

As long as the foreclosure was a 1st, and done properly, you will have “clear” title except for any HOA fees and current/back property taxes, maybe some utility bills.

If I am utilizing a LOC against an investment portfolio @ 4.25% Interest with no term, and financing the entire deal, would my Cash on Cash be determined by dividing my annual revenue by what I paid annually to carry that LOC debt? 

Qualified Opportunity Fund is an investment vehicle that is set up as either a partnership or corporation for investing in eligible property that is located in an Opportunity Zone and that utilizes the investor’s gains from a prior investment for funding the Opportunity Fund.Q.

Additionally, they have restarted the public water/sewer expansion project and will have most of the city on pubic utility within the next 10 years.