I am interested in getting an approximate value multiplier.

Then, multiply and divide by the 70% and subtract how much the repairs will cost? 

The 2% Rule is the same thing as using the 50% Rule and applying a 12% Cap Rate on the annual NOI.I was looking at some properties and noticed I got the same value using the 2% rule and using the 50% for an estimate of NOI and happened to be using a 12% Cap.Being a math dork I did write it out symbolically and they both reduce to the same mathematical equation (Which BTW is just multiply the monthly rent by 50).

Houses are selling very quickly here, but I would guess that will come to a stand still in the near future as infection cases quickly multiply over the next couple weeks.

As @David Krulac pointed out, the county assessed gets multiplied by a county specific common leveling ratio (CLR) that the PA Department of Revenue publishes periodically.For inheritance tax purposes, the valuation is for the date of death of the deceased borrower, so one would use the CLR for that county from that time period to establish the value.

Try working the numbers backwards to see if a property is worth  chasing;Take FMR * 12mo * GRM to find max FMV that a unit could still provide a positive NOI.Frm (fair market rents) isn't too hard to find, but GRM(gross rent multiplier) is intuitive magic number 10 or less. 

Purchase Price: $100,000.00 Purchase Closing Costs: $2,500.00 Estimated Repairs: $0.00 Total Project Cost: $102,500.00 After Repair Value: $120,000.00 Down Payment: $20,000.00 Loan Amount: $80,000.00 Loan Points: $0.00 Loan Fees: Amortized Over: 30 years Loan Interest Rate: 4.500% Monthly P&I: $405.35 Total Cash NeededBy Borrower: $22,500.00 Monthly Income: $850.00 Monthly Expenses: $840.35 Monthly Cash-flow: $9.65 Pro Forma Cap Rate: 4.15% NOI: $4,980.00 Total Cash Needed: $22,500.00 Cash on Cash ROI: 0.51% Purchase Cap Rate: 4.98% Total operating expenses: $435.00 Mortgage expenses: $405.35 Vacancy: $42.50 Repairs: $42.50 CapEx: $85.00 Insurance: $80.00 Management: $85.00 P&I: $405.35 Property Taxes: $100.00 Financial Info Income-Expense Ratio (2% Rule): 0.83% Total Initial Equity: $40,000.00 Gross Rent Multiplier: 9.80 Debt Coverage Ratio: 1.02

There are a few areas that you need to analyze: Operating Revenues, Operating Costs, Repair (one-time) costs, and Financing options.I would start by looking at the after-repair rental rates for both 2 and 1 bed units, multiply that out by your 10 (2 bed) and 10 (1 bed) units to get a total monthly revenue.Then, figure out the cost of repair per type of unit (~10-15K/unit depending on finishes and extent of repairs necessary) Figure out the cost of repair for common areas (exterior, hallways, parking, main utilities, etc).Use common metrics for operating costs (10% management fee, 10% repair, 10% vacancy etc, 10% capex, etc.)Then figure out the NPV of the deal with both of the financing options to see what works better for you.

Multiply that by .45 = $900.  

Add the Gross Multiplier $4800 per year x 13 Gross Multiplier and the value of my property increased by $62,400 + $48,000 in 10 years means when my tenant gave me a notice to move I just made $110,400 plus add 4% rent increases for the 1-year period and the Gross Multiplier kicks in plus the additional rental income and when the tenant gave me a notice to move I made about $250,000 in 10 years.