Multiply that by 32 units.  

I know when wholesaling a single family house, you make sure to deduct the 4% from the end buyers purchase price..Do I multiply 4% x 6 and deduct that from the purchase price ?

I would divide 180k by 2 then multiply the 90k by lets just say 1% to get the amount of rent i should charge each tenant right?

Gross Rent Multiplier Method (GRM) - purchase price / gross annual rent (annual rent as if property is 100% occupied), this give you the GRM.

Can't take the best decade of RE (and stock) appreciation ever and simply plug in that rate and multiply by the number of extra investments you think you could've purchased but we're too busy dealing with tenants.Unless you were buying all cash.

That money will multiply and allow you to buy something big later on.

One time I had an appraiser adjust 5-10k for better GRM (gross rent multiplier) but that was a unique instance.In most cases where I used conventional lending or local commercial lending for 1-4 from credit unions and community banks they still ordered a local residential appraiser.Once you get to 5+ and above you'll be able to capitalize more so on the income and cap rate valuation methods which regard you much more for being a good operator. 

Annual operating expenses = annual taxes+insurance+utilities+HOA fees+lawn/pests+vacancy+repairs+property management  (i.e. does not include CapEx or mortgage)NOI = annual gross income-annual operating expensesCap Rate = NOI - purchase pricePro Forma Cap Rate = NOI / after repair valueCash on Cash ROI = total annual cashflow / total invested capitalTotal Initial Equity = (down payment + closing costs + estimated repair costs) + (after repair value - total cost of project)Gross Rent Multiplier = purchase price / annual incomeThat is a lot of formulas!

What I see alot on larger houses without equivalent comps is they take the price of a smaller house, calculate price per square foot and do some multiplying with the larger square footage.

All hypothetical numbers but multiply the comps by 80% and that's what the lender should be cashing out at.