The municipality first: it decides who pumps
In Quebec, pumping a septic tank follows a provincial regulation on wastewater from isolated dwellings (Q-2, r. 22). The municipalities of Saint-Augustin-de-Desmaures and Val-David restate its rhythm: at least once every two years for a tank used year-round, and at least once every four years for a seasonal one. Who does the pumping, though, changes from one town to the next.
In Saint-Augustin-de-Desmaures, only the contractor authorised by the town may pump within its limits, a mailed notice announces the week of the pumping, and a date for an extra pumping cannot be booked. In Val-David, the owner has the tank pumped, then gives the town the invoice or the contractor’s attestation. So your receptionist asks for the municipality before promising anything, and she does not go around a designated contractor.
The rest of your phone looks like a project trade: a new system on a building lot, a field to replace, an inspection before a sale with a notary waiting. In Quebec, installation falls under a licence subclass of the provincial building authority (2.4, private sewerage systems); in British Columbia, the work belongs to practitioners registered with ASTTBC. She records the permit and the site assessment if they exist, machine access and the deadline, and prices nothing before you have seen the site.