What moves the price
- Pumping included or not
- Risers present (faster, cheaper) or a buried lid (digging)
- Pump chamber or ATU (more components to test)
- Hydraulic load test requested (extra, but definitive on field capacity)
For a home purchase, insist on: tank pumped and inspected, distribution box checked, drain field probed, and the county permit drawing pulled. A $200 "visual" that never opens the tank is not an inspection.
Neither Texas nor the county requires an inspection at sale by statute; lenders and buyers' agents usually do. See septic inspections for what's covered.