I think Plymouth County is the sweet spot with a good balance between prices and rents.Brockton is a good target, though there's a war zone in the center and somewhat to the east. 

Creating numerous LLC's for a growing portfolio will eat up much of your margins at a minimum 800 dollar annual filing fee per LLC. 

And the correction will be triggered by outside forces affecting real estate (corporate debt, student loan debt, international policies that affect outside investors, trade wars, etc).  

Finally, for foreclosures on the MLS, please note that if the property is less than $100k be prepared to get into a bidding war with other actual cash buyers unless it’s not a good deal (where you can be all in for 70% of ARV).

No one formula works because each situation is unique.For example, the value will be determined by these variables, as well as numerous others : likelihood that note can be made re performing, amount of time in default, owner occupied or not, stage of foreclosure, foreclosure laws of the state property is located in, if the debtor has filed bankruptcy, financial condition of debtor, whether or not there are any guarantors, type of area the property is located in, equity in the property, balance of the note, interest rate of note, default rate of interest, communications with borrower, residential or commercial, if residential was the note in compliance with Dodd Frank, did it pre date Dodd Frank, or was it an exempt note, note documentation, chain of title, availability of original documents, robo signed or individual signed, title insurance.

Sounds like a great deal, barring it isn't in a "war zone"!

UNLESS they have very big war chest ( liquidity) ... 

CAM is usually factored into the regular monthly payment.Capital improvements typically fall on the owner but again it all depends and I have seen it done and numerous ways.

She listed the property in the MLS and after a few offers came in we ended up winning the bidding war at $118,500 with the listing agent going to bat for us.

@Lance Hummel welcome to Bigger Pockets,I see there has been numerous discussions on this topic, if you don't get a reply try the search function.