If investors in your market always look at a multiplier or the income approach then that would be the best indication of value. 

If you have a Short Term Rental in Missoula, or know someone who does, the city is planning some pretty significant changes to the regulations, including limiting their numbers, multiplying the fees by 7X, and many more.

I'm using the flat percentage of ARV method to come up with an offer price for a property which just multiplies the ARV by a certain %.

Then multiply and add up. 

How would you go about accumulating multiply rentals with this strategy? 

Multiply by 24 monthsCurrent value minus mortgage, real estate commission, $2500- 3000 in title and sales expenses what is that number?

For example, if the property was purchased for $200,000, the cap rate would be calculated as follows: Cap rate = $14,000 / $200,000 = 7%.Gross rental multiplier (GRM): The gross rental multiplier is a quick way to estimate the value of a rental property based on the income it generates.

The cash flow (NOI) is just the numerator in the equation, you have to finish the math.As far as the time to payoff the property, this is generally measured by calculating the Gross Rent Multiplier.

What about Gross Rent Multiplier? 

This is a performance metric used in the hotel industry and is calculated by multiplying a properties average daily rate (ADR) by its occupancy rate.