Mold Testing for Real Estate Agents

You have a contingency window, an inspector who flagged suspected growth, and two parties who are now imagining very different numbers. What you need is a document, fast, from someone who has no reason to make the number bigger.

We test only. We do not perform remediation and we take no referral fees from remediation companies. That means nobody walks into the middle of your transaction and hands your client a $14,000 estimate ten minutes after finding something. We take a measured volume of air, send it to an accredited lab, and write down what came back. Then we are done.

Base inspection is $425 including one indoor air sample plus an outdoor control. Rush lab turnaround is 24 hours for an additional $100.

Working inside a contingency window

Most inspection contingencies in this market run seven to ten days. Here is what that looks like against our actual timeline.

Tell us the date you are working toward on the first call. If the timeline is not achievable we will say so immediately rather than letting you find out on day six. That is the single most useful thing a vendor can do for you.

Volume context, if it is useful: roughly 5,800 to 6,300 homes sell per year in Spokane County, and 2,484 sold in Kootenai County in 2025 at a median of $549,000. Median owner-occupied value is $410,700 in Spokane County and $518,700 in Kootenai. These are transactions where a $425 test is a rounding error against the risk it resolves.

What a clean report does for a deal

It replaces a rumor with a document. "The inspector said there might be mold" is unpriceable and unnegotiable. A report showing indoor spore counts not elevated relative to the outdoor control, with moisture readings to match, is a fact both sides can stop arguing about.

It bounds the problem when there is one. If something is found, the report documents where the wet material actually is. That gives whoever writes a remediation bid a defined boundary and gives your client something to measure competing bids against. Vague findings get expensive bids.

It stops a price reduction from being invented. A buyer asking for $20,000 off for mold and a seller offering nothing is a negotiation with no anchor. Test data plus contractor bids against a defined scope creates one.

It closes the question for the next transaction. A seller who tests and gets a clean result has a document to hand the next buyer, and the one after that.

It is not written by someone bidding the fix. This matters more in a transaction than anywhere else, because the other side's agent will look at who produced the report. A report from a company that also quoted the remediation invites the obvious objection. Ours does not.

Disclosure, handled carefully

We are not attorneys and we do not advise on disclosure. Talk to your broker or counsel. What we can tell you is what the forms exist to do.

In Washington, the seller disclosure statement under RCW 64.06, the Form 17, asks sellers about known defects including water and drainage issues. In Idaho, the seller property disclosure form required under Idaho Code Title 55, Chapter 25 covers similar ground. Both are knowledge-based documents. What a test result means for a specific disclosure obligation is a legal question that depends on timing, knowledge and the transaction, and it is not one we answer.

One practical note that comes up constantly: neither Washington nor Idaho requires mold testing, and there is no state or federal numeric standard for airborne mold. Nothing "passes" or "fails" a legal limit, because no limit exists. A report compares indoor conditions to the outdoor baseline and documents moisture state. Describing it accurately in a transaction is safer for everyone than describing it as a pass.

What we do on site

• Air sampling with a calibrated pump drawing a measured volume through an Air-O-Cell or Allergenco-D spore trap cassette, sent to an accredited lab for direct microscopic examination
• An outdoor control sample on every job. Outdoor air always carries spores, so an indoor number in isolation is meaningless. Elevated means elevated relative to outside, same property, same day. Reports that omit this cannot support a conclusion and will not hold up when the other side reads them
• Surface sampling by swab or tape lift on visible staining, which is often the whole question: is that growth or is it a dry water mark from a repair made in 2004
• Moisture mapping with pin and pinless meters
• Thermal imaging to read temperature differentials behind intact drywall without cutting anything
• Borescope into wall cavities when we need to see rather than infer
• Psychrometrics by area and outdoors: relative humidity, temperature and dew point
• A written report with photographs, readings, lab data and chain of custody

We work both counties. In Spokane County, roughly 27% of housing in the city was built before 1950 and single-family detached homes average around 70 years old, so crawlspaces, vapor barriers and old plumbing dominate the findings. In Kootenai County, Coeur d'Alene averages 26.6 inches of rain to Spokane's 17.2, and the failure modes lean toward hillside walkouts, lakefront lower levels and fast-built newer subdivisions.

Pricing

Why the independence protects your transaction

Washington's Department of Health says plainly that there are no certification requirements for mold work in the state and that anyone can call themselves a mold specialist without training or credentials. Idaho is the same and licenses neither mold work nor home inspection.

In that environment, most companies advertising mold services also sell remediation. Put that company in the middle of a live transaction and you have a vendor with a direct financial interest in how alarming the report sounds. New York banned one company from both assessing and remediating the same job under Labor Law Article 32. Washington and Idaho have no such rule, so the separation is voluntary.

We also keep health language factual, which keeps it out of your negotiation. CDC has never established a causal link between Stachybotrys and serious illness, and says no test proves an association between a specific mold and particular health symptoms. Documented effects are allergic reaction, asthma triggering and upper respiratory irritation in sensitive people, plus serious infection risk in the severely immunocompromised. Nobody is going to be told their family is in danger by us.

Agent questions

How fast, really? If you call Monday with a Friday deadline, that is normally achievable with rush lab. Tell us the date first, not last.

My seller wants to test before listing. Is that smart? It is a strategy question for you and your client, but the mechanics favor it. Knowing before a buyer's inspector finds something is a better position than reacting to it during a contingency period, and a clean report is a marketing asset. If the result is not clean, your client controls the timeline instead of a buyer controlling it.

The house has an unfinished crawlspace with no vapor barrier. Is that automatically a finding? No. It is a condition worth noting and a common one in Spokane's older stock, but whether it has produced actual growth is what the meters and the samples determine. Plenty of dirt crawlspaces test unremarkably.

Do you write repair estimates? No. We do not remediate, so we do not bid remediation. We can tell you what the report shows and hand your client several contractor names we are not paid by.

Can you do clearance after the seller's remediation, before closing? Yes. $375 flat for up to three samples, 45 to 60 minutes, including a visual check of the remediated area and containment plus air samples inside containment and an outdoor control, evaluated against IICRC S520. Schedule it while containment is still up. A contractor clearing their own work is grading their own homework, and a buyer's agent will say so.

Who does the report go to? Whoever engages us. If a buyer hires us, it is the buyer's report to share or not.

Get a test on the calendar

Call with the address, the deadline, and what the inspector flagged. We will tell you what it costs and whether we can hit your date before you commit to anything.