Anyone have a rough idea what the cost per unit is for owner-paid water/sewer/garbage in Sacramento? It’d be for a multi-family property consisting of 1 bdrm units. 

You can look up the rates for water, sewer and storm drain. Here is a link. You'll want to clink on the separate links for water, sewer, and storm drain. If you end up with a PDF with many different rates for different sizes and types of properties, you are in the right place.

https://www.cityofsacramento.org/Utilities/Services