Based on the range of these GRMs, choose a number that seems most appropriate (some appraisers will simply average them all together - others will just choose a number) ... take the GRM value you've decided to use and multiply it by the monthly rent you expect for the duplex you are pricing out - this will give you your "income approach" value.Now, you look at the two values you've just generated and use your best judgement as to which is most accurate - or it might be a blend of both.To give you a real-world example of this, some clients of mine just closed on a duplex in Raleigh ... the appraisal came back with $468k for the sales comp approach - $594k for the income approach - and $480,200 for the replacement cost approach ... the appraiser selected $468k as the market value.Hope I made this clear enough for people to follow and understand...

The multiplier is usually derived from the sales comps that were analyzed. 

@Dona Cardenas To estimate the rehab cost, multiply the square footage of the property by the rehab cost per square foot.

3. multiply the rent by 504. if the all-in cost (PITI+vacancy+maintenance+management+incidentals) is about the same price, you likely have a good cash flow property.5. sales 101: every profit is a good profit. maybe it's only one cent, if so, do thousands more.      

When you are doing that rough calculation multiplying monthly rent x 60 to get max price you will pay (including any rehab costs).

I basically took the $82K figure and multiplied it by .65 (which accounts for a 5% ARV fee for you) and I subtracted $15K for repairs.

The rental income specified on the lease, multiplied by 75%, is to be greater than the PITI on your departing residence.

Some valuations are done as a multiplier.

I multiply that number by $200.

Kelly,I do not understand why you are multiplying the  lot rent  by 70.