Better to have a month's vacancy than to suffer multiply months of no rent while having to deal with evictions.

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 ?

Deceive the seller and watch your problems multiply!

Multiply that by 20 and you will be in serious trouble.

I make sure the sq. feet is within 150 of each other, and I make sure the year built is close together.After that I calculate the average price per sq. ft. of the comps and multiply that by the sq. ft. of the property.  

I think the inherent flaw in your calculation is adding your "profit" after already multiplying by .70 Your profit is in already the 30% spread.

So if we have $75,240 in annual income, multiply that number by (1-0.45) 0.55 to get an estimated NOI of $41,382. 

(Actually, that'd be really cool if practical: some sort of multiplier to apply to his numbers for major metro areas.

Investing is about multiplying your money, right?

Higher price = bigger loan = higher mortgage payment = less cash flow when rented.More Units = More Cash Flow -- I recently completed a thorough analysis of the multifamily properties available in the Sacramento area, and the only properties that passed the 1% Test (monthly gross rents close to 1% of purchase price) or had a Gross Rent Multiplier of 10 or below (time in years it would take for property's gross rents to pay for the purchase price of property) were all multifamily units, and more so 3-4 plexes.Financing is the Same as Single Family Home -- there's no added loan requirements, and you can still qualify to purchase the property with FHA or VA loan if you so choose (thank you for your service by the way!)