A room may smell smoky without a visible black coating, while another has obvious soot that wipes onto your finger. Neither observation alone tells you the full cleanup scope.
The way smoke traveled, the materials involved and what surfaces absorbed residue affect what a professional should inspect. A fragrance is not a substitute for source removal.
Visible residue is only one clue
Soot can settle on walls, ceilings, shelving and contents; smoke can also move through open doors or ventilation paths. An assessment should map the affected rooms and test cleaning methods on appropriate surfaces. Rubbing dry residue without a plan can smear it or push it into porous material.
Ask what is causing the odor
Odor can persist in unfinished wood, fabrics, insulation and other materials. Ask what source is suspected and whether it can be cleaned, sealed after cleaning or must be replaced. HVAC concerns require an explanation of what was inspected and why any duct or equipment work is proposed. A one-size-fits-all deodorizing treatment may miss the source.
Clean first; evaluate what remains
A reasonable sequence is safety clearance, documentation, residue assessment, cleaning or material removal, and a final review. Method and equipment should fit the material. Ask a vendor to distinguish test cleaning from guaranteed results; some delicate items and finishes may not be restorable.
What to put in the work authorization
List affected rooms, surfaces, contents, any HVAC work, testing or post-cleaning review, and change-order rules. If a provider proposes sealing a surface, ask why cleaning alone is insufficient and what material will be sealed. Keep before-and-after photographs and an itemized invoice.