@Silas Rogers If you haven't already, I'd highly recommend reading the house hacking article on BP, that's what I referenced when I first learned about house hacking.
https://www.biggerpockets.com/blog/2013/11/02/hack...
For my market I wasn't looking too hard for small multifamily because they are pretty scarce and are often in C/D class neighborhoods which I didn't want to live in. Honestly I did not buy my first house with the intent of house hacking, I mostly just really needed a place to live at the time. That being said I specifically looked for either houses/townhouses that were 3B2B or 2B2B (with the ability to easily add a 3rd bedroom on) and I wanted a max purchase price that was ~75% of the largest loan I actually qualified for.
I found my current place on MLS through my realtor after touring a bunch of house and honestly I got really lucky. The numbers ended up working out great for me even though I hadn't specifically been using the 50% rule or anything. Looking back (and towards the future as I am analyzing my next deal specifically for a house hack) the biggest factors I'd consider are:
1. Average rent in the area you're looking to house hack in -- don't high ball or low ball what you'll actually be making on rent. A friend of mine high balled the amount she'd be getting per month and ended up getting rid of the rental property rather than having negative cash flow every month.
2. What amount of rehab you want to put into the property since you'll most likely be living there while you're upgrading. I went for light rehab because due to lack of funds I knew I'd be doing a lot of the rehab myself.
3. Max purchase price and if the property fits into the 50% rule when you have roommates. See the above article for details on the 50% rule.
4. What type of property makes sense in your area and what are you going to be happy with. As I mentioned before I didn't really consider small multifamily BUT I already have friends lined up to live with me so I wasn't concerned about sharing my actual house with a stranger, I don't think I'd be comfortable renting out a room to 2 random people.