Converting a SFH into a Legal Duplex in Salt Lake County

[Chloe Dawn Murphy]

I'm looking to purchase a single family home that has a separate entrance to the basement in salt lake county, specifically Midvale, Murray, or Sandy. I want to convert it into a duplex by adding a kitchen in the basement. It would be purchased as a owner occupancy for house hacking. What are some potential road blocks I might encounter with legality, permits etc? Does Utah County have better "laws"?