Remove tenants, rehab and rerent?

[Greg Clark]

I have a duplex under contract which I plan on house hacking. One side is already vacant. The other side is rented, but it's rented at about $200-250/month less than I could rent it if I fix it up inside. I'd probably spend about $6k to make it pretty.

Any thoughts on how to run those numbers to determine if it's worthwhile?

My first thought is to do something like: (increase in rent * 12) ÷(cost to rehab + vacancy and re-rent expenses) to get the cash-on-cash return (COC of this slice of the deal). In this case, that ends up being about 30%, so great deal, right? Or did I miss something?