The offer
Unlimited vents, whole house, $79. Sometimes $69. It runs on social media, in mailers, and on discount sites, and it is one of the most reported home-services complaints in the country.
Nobody can clean a full duct system properly for $79. The equipment alone — a truck-mounted or portable negative-air machine — costs more than a day of that work. The price is not the product. Access to your hallway is the product.
The script
Step one: the visit is short and the equipment is small. A shop vacuum and a flexible hose, one register at a time. No negative-air machine, no access cut into the trunk line.
Step two: something is found. Mold is the usual one. You will be shown a photograph — sometimes of your system, sometimes not — and told there is contamination that the basic service does not cover.
Step three: the price becomes four figures. An antimicrobial fogging treatment, a sanitiser, a 'deep clean' upgrade. The quote lands somewhere between $700 and $3,000, and it is presented as urgent and as a health matter.
Step four: the pressure. Today only. The crew is already here. The van leaves and the price goes up.
How to shut it down
Ask for the inspection before the sale. A camera in the trunk line, on a screen, in your house, showing your ductwork. Any real technician can do this. Photographs on a phone that could be from anywhere are not evidence.
Refuse chemical fogging on the spot. The EPA's guidance on sealants and chemical biocides in ducts is that homeowners should not permit their use as a matter of routine, and that they have not been sufficiently researched for this application. It is never an emergency decision.
Get the number of access points. A genuine whole-system clean requires cutting and sealing access into the supply and return trunks. If nobody is opening the trunk line, nobody is cleaning it.
Ask what happens to the price if they find something. In writing, before they start. A company that will not put a ceiling on the visit is telling you what the visit is for.
What honest pricing looks like
A real whole-home duct cleaning in most US metros runs from the low hundreds to around a thousand dollars depending on the size of the system, the number of returns and the access. It takes a crew several hours.
We quote per home after we know the system, and the quote does not change unless you ask for something more. If a technician finds something genuinely outside the scope, the job stops and you decide — nothing gets added to an invoice you have not agreed to.