So companies that, instead of producing stuff, offers a service are what I looking into. What are their Tier limitations?
There are no tier limitations in terms of what they can do or how to roleplay them.
I am able to turn every interaction into some sort of business contract, agreement, networking, construction of facilities, hiring of new personnel,an auction, and expo, a fundraiser --- literally any thread can be used to market a service company.
I'd say it is easier to tier up service companies than straight up production companies that focus on contracts on products, but that's just me.
Granted, I enjoy tiering up companies so it is pretty easy for me to tier up service companies like ATC,Southern Systems Business Bazaar, Yum Bunnies Restaurants, etc.
Enjoy and have fun; service companies are a blast.