How to tell if an owner occupy duplex is a good deal?

[James Lapierre]

Hi BP community!

Brand new here, been searching for my first property. I've been looking at duplexes (or more) to owner occupy. I was pre-approved for 350k conventional or FHA. I've been trying to find deals that will benefit me 3-4 years down the road when I move out and rent both units, here's my question: is there an equivalent to the 1% rule when owner occupying?

I'm looking at this duplex with MLS list price 330k which I think is way too much, it was listed at 249k a couple years ago. 2BR 2B units, Rents about 1800. I'm stuck finding a simple equation for owner occupying, what did you do for your first duplex if you lived in one half first? How did you know it was a good deal? sorry for the newbie question!