How to determine value of duplex?

[Kevin Krysty Jr.]

Hey ya’ll. My wife and I currently live in a duplex, with another one behind us on the same lot (4 units in total). We are currently paying $550/month in rent, and were considering house hacking with the idea of buying and then renting out the other units. This have been difficult for me because I have not yet done a transaction, I’ve sold some homes as a Realtor, but I feel like with how appreciated our market is, the price I would pay for the 4 units would be higher than the rent (unless new paint, carpet, and appliances were added - then I could increase the rent)...my biggest area of difficulty though is the MATH. I’m good at it, I just don’t know where to get the numbers from? How do I price a 2 BR 1 BA duplex? Because to my understanding, anything less than 5 units isn’t considered a multi-family, still a single-family. So I’m pretty lost, have great ambition to purchase this property...I just need hard numbers and I do not know what that looks like. Any and all insight is appreciated. Thank you.