Multifamily cost structure and scaling template

[Sean Brady]

Hi Everyone. I was wondering what Investors/ Landlords thoughts on Multifamily's cost structure. I am a Realtor on Long Island who has a bad tenancy to spend more time looking at investments than marketing. So recently I created a Financial Analysis template that would automate my decision making process, generate marketable Pro Forma Financial Statements (Still somewhat of a work in progress). My template came out nice but, its really primarily for me to use for wholesaling Single Family Residence. My various costs expenses on the template are a percentage of the rent. I ran those numbers also based on what my research told me it was for my local market. Anyway here is what I got. (In advance I know some of the variable expenses are fixed and the fixed are variable.)

Fixed expenses:

Electricity .04653

Water and Sewer .0167

Garbage .0352

Property taxes

HOA's .05

Heating .045

Monthly insurance .024

PMI .01

Variable Landlord expenses

Vacancy rate .06-.09

Repairs and maintenance .02

Capital Expenditures .08

Management fees .083

Depreciation (1/27.5)

My question is this. First if anyone disagrees with what my percentage allocation is please let me know. Second, when looking at a Multi Unit Family investment what costs scale with the properties? Are there any rules/ Principles I can use to put into another automated template that would help me analyze the investment? The idea of creating Multi-Unit Apartment buildings/ Multi Family Buildings is to lower fixed and variable cost through an economy of scale. While not every cost is going to have this feature are there any that do? 

I know I need to spend more time Marketing as a Realtor but, I also need to be looking for deals for my investors. I feel like my Single Family Residence Analysis template has actually been pretty good in determining fair value. Obviously everything in the formula is garbage in, Garbage out but some ideas here would be appreciated.

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