Does the seller have an attorney handling?

If you can't handle waiting for the money to be earned, you're in the wrong profession.

Try to reduce asking price but yes.

Nephtalie, While many of my friends will disagree - I don't mean to be a "Debby Downer" but.....Representing a mortgagor(ower) to help reduce/modify a loan with a Mortgage(lender/bank).  

I also add in all of the potential rehab costs (up to 15-20k rehab estimates), thus utilizing little or no of my own money, nearly completely leveraged.When I do that, the cash flow on these properties become quite low and I’m likely needing to reduce my offered purchase price to make my requisite 100/mo cash flow. 

Affordable Housing Incentives - The city of Oakland will reduce set back requirements to build on a lot, and actually increased the number of permitted units above the zoning limits if you build a certain % of affordable housing units into the building, and commit to keeping the rental units in a program like section 8 for 55 years ( see here).

3A Realty Group in Quincy handles my rentals.

However, there might be some tax benefit in your situation to treat this as a partnership (LLC tax as a partnership ).For instance, this treatment could reduce a married couple's SE tax bill when one spouse has wage income above the Social Security tax ceiling ($128,700 for 2018).

Should I stick to the ARV formula of 70% on the dollar, and then reduce it further by the rehab costs?

The S corp I own, along with the fact that my wife and I are the only two employees, has allowed me to open a SOLO 401K to reduce taxable income.