The Downtime Rules from Ultimate Campaign include rules for running buildings and organizations during downtime. One of the phases is the upkeep phase, which reads:
Phase 1—Upkeep: Pay costs associated with maintaining completed buildings and organizations.
Step 1—Add Up Costs: These costs include ongoing or recurring costs for your buildings, organizations, and other previous downtime activities that have accrued since the last time you have had a downtime session. Most of these costs are incurred daily, whether or not you are spending downtime days at the settlement.
However, I don't see anywhere that describes what the recurring cost of a building or organization may be, besides hiring a manager. If one does not hire a manager, is there any other recurring gold upkeep required to maintain a building or organization?