What I did for the data bus is to run a direct burial cat-5e cable (Superior Essex 22 gauge part number PW52-846-75) between our house and shop (110 feet apart), the idea being to minimize signal degradation on the long run.
The house and shop are wired with standard 24 gauge Cat5e. There is underground PVC conduit between the two buildings, each end terminating in an exterior junction box. Standard and underground meet in the junction box and are terminated using RJ45 connectors. The cable ends each plug into a grounded ethernet surge suppressor at both buildings. Note that the 22 gauge cable probably uses different connectors and crimper to accommodate the thicker conductors than standard 24 gauge cable. I used ICC connectors and crimpers.
Ethernet surge suppressors are these:
https://www.amazon.com/gp/product/B00805VUD8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I don't know, for a fact, that these surge suppressors are really effective in this RS-485 application but they don't seem to hurt. My original plan was to use optical isolators between underground and house/shop at each end but they didn't work. My goal is to find out why the optical isolators didn't work, and fix if possible, but it's down the list a way.
In the remote shop the data bus connects to an Elk P212S which supplies power and battery management for the devices you place there. I have input and output expanders there for motion sensors, water leak sensors, man door and overhead door sensors, and heat and CO sensors.
That's about it. It's been working fine for six months now.
The only suprise was my error. The house has a whole house backup generator, the shop does not. During a 5-day power outage the P212S battery got low and shut off (as it's supposed to), triggering a lot of alarms in the house that is powered by a generator. So I need to come up with a way to keep that panel powered during outages.