Number breakdown for a owner-occupied Duplex

[Lindsay Damici]

Hi BiggerPockets Community,

I need some advice. I am currently searching for duplex/multi-family property (I am first-time homebuyer looking in the Burlington, VT area) and I really want to take a close look at the numbers and make sure they work for an investment property. I find myself wanting to spend more money, but I'm not positive if the numbers will work out.

Does anyone have an excel sheet or format they can share that would help me make sure I am taking everything I need into consideration?

I am planning on airbnb(ing) the other half of my home and need to figure out how much I need to make (on a yearly basis) renting out the other half if the home is $250,000, $275,000, $300,000.  My goal would be to have the rental income pay for the entire mortgage and if I make more than estimated that can help with all the other items - I just need to figure out what are my estimated out of pocket costs on a monthly/yearly basis. 

List of items I know I need to account for: 

• water
• trash
• recycling
• heat
• internet
• electric
• Vermont Gas rental (depending if the unit it rented, but based off of what I have looked at most are - around $17 per unit a month)
• yearly taxes
• random repairs/updates/discretionary funds (this # is important for me to know because many of the duplex's in my purchase price range need a decent amount of work done on them)

I just have a feeling I am forgetting something and would love to see how others calculate their costs. 

Thank you!

Lindsay