Align capacity, energy, venting, water, drainage, electrical, and permit rows

Provide current model, capacity, energy source, age only when documented, symptom, hot-water pattern, occupied units, fixture demand, utility constraints, and planned remodels. Do not open the unit.

Compare equipment, sizing basis, water piping, isolation, relief and discharge, drain pan, expansion control, gas, venting, combustion air, condensate, electricity, controls, removal, permits, startup, and test.

Ask which licensed parties perform plumbing, gas, electrical, chimney, HVAC, and building work; how shutdown is communicated; and what concealed or code condition can change price.

Retain model and serial, permit and inspections, startup record, professional settings, manuals, warranties by issuer, maintenance, removed-unit disposal, and open chimney, electrical, gas, or finish items.