Hey @Talya Reynolds and welcome to the forums! There are a lot of different approaches to calculating a "good" investment. Since you will be house hacking, there are a separate set of factors coming into play that will drive this decision. A bad deal for a traditional investor could actually be a great deal for a new investor that is house hacking. Here are a few tips:
1) Rent savings - How much per year will you save on paying down someone else's loan vs paying down your own? Even if you aren't cash-flowing in year one, this does not necessarily mean it's a bad deal.
2) Use sites like Zillow and FB Marketplace to figure out what people in your area are paying for rent and compare those places to your target property. This should give you a good idea of what to expect in year one and also after you move out. Think long-term when looking at numbers.
3) Use the BP Calculator on this site to run the numbers. Will the rent cover a good amount of your mortgage while living there? What will the numbers look like when you can rent out both units?
4) Connect with investor-friendly realtors/lenders. They will have resources, tools, and insight for you that are specific to your market.
I could write a book but for the sake of time, my biggest recommendation is to connect with other investors close to you!