So the unit is occupied and cared for.

The easiest way to accomplish this if the home is fully occupied would be to provide one of the tenants a notice to vacate immediately after you take ownership of the property.

Salt Lake I believe is from 1995 if it were to be used as separate units non-owner occupied.  

Nothing less than that even with owner occupying one of the units.

I did some digging and it looks like the new law doesn't apply to “owner-occupied properties with three or fewer units, owner-occupied single-family homes." 

., but I’m not sure if that still makes sense.During the closing process I learned that the property was still occupied by the previous owner that was foreclosed on and that her and her boyfriend were drug addicts and at least one of them had a warrant out for their arrest.

This strip was built in 2018 and we bought in mid 2019 and soon after we bought we found out that previous owners were giving this tenant 20-30K in TI and all kinds of promises to get him to sign (of course they then raised the base rent higher) so they made the strip 100% occupied and raised NOI. 

If you'll be occupying part of the property and renting the rest, that also implies it's a multi-family property, which implies there will be common areas that you'll be responsible for maintaining. 

I’m curious as to how as a new owner and landlord (at least till my portfolio grows) one goes about introducing yourself to the occupying residents and setting expectations and or getting know the situation of the property you bought.

If it's an investment property, rates may not be as favorable as on owner occupied.