Define the same job before comparing price
Give each provider identical workforce facts and required responsibilities. Separate recurring fees from setup, data conversion, software, payroll events, handbook work, investigations, benefit projects and transition assistance. A lower quote may simply include less work.
Model first-year and ongoing cost
Calculate a normal month, a busy month and the full first year. Review minimum fees, headcount changes, annual increases, optional work, renewal and exit charges. Compare cost with internal staffing, systems and management time without assuming either approach is always cheaper.
For related guidance, read HR outsourcing pricing models and HR outsourcing cost guide.