How do I verify a pressure washing contractor's insurance?

Ask for a Certificate of Insurance (COI) sent directly from their insurance agent — not a photo from the contractor's phone, which can be expired or doctored. The certificate shows liability limits ($1M is the professional standard) and effective dates. Any legitimate contractor can have their agent email it the same day; hesitation is your answer.

What should a written pressure washing quote include?

Surfaces and square footage covered, the method per surface (soft wash vs. pressure), what's protected (plants, fixtures), any guarantee terms, total price, and what's excluded. A number texted with no scope means change-orders later or corners cut on site.

Is a cheap pressure washing quote a red flag?

A quote dramatically below the local range usually means no insurance, no guarantee, or high-pressure-on-everything methods that risk siding and roof damage costing far more than the savings. Know the local price ranges before you shop so you can spot both gouging and too-cheap-to-be-real.

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How to Vet a Pressure Washing Contractor 12 Questions That Separate Pros From Rented Machines

By the Up North Pressure Washing crew · Duluth, MN · Updated June 2026 · Print this checklist

Yes, we're a pressure washing company publishing a guide on how to interrogate pressure washing companies — including us. We're doing it because every spring we re-wash jobs that were "cleaned" a month earlier, and quote repairs for siding that a $200 special destroyed. The barrier to entry in this trade is a rental counter and a Facebook page. These 12 questions sort the field in one phone call, and we've included the answers that should end the conversation.

The Damage-Prevention Questions

1. "What pressure will you use on my siding?"

Pro answer: "Siding gets soft washed — low pressure with a cleaning solution." May reference specific PSI under ~1,000.

Walk away: "We'll blast it right off" / "full pressure, that's how it gets clean." That's forced water behind your panel laps and February mold. (The PSI chart — share it with whoever quotes you.)

2. "How do you clean asphalt shingle roofs?"

Pro answer: "Chemical-only soft wash, never pressure — pressure voids shingle warranties." (Manufacturer positions here.)

Walk away: Any mention of pressure washing a roof, or a surface cleaner on shingles.

3. "What's in your cleaning mix?"

Pro answer: Names sodium hypochlorite percentages and a surfactant, plus how they adjust by surface. Pros talk chemistry comfortably — it's most of the job. (What's actually in the tank.)

Walk away: "Trade secret" / "just soap" / visible confusion.

4. "How do you protect my plants and landscaping?"

Pro answer: Pre-soak with water, covering or rinsing during application, post-rinse. A specific routine, not a shrug.

Walk away: "The chemicals are totally harmless." They're not — they're managed.

The Accountability Questions

5. "Can your insurance agent email me a COI?"

Pro answer: "Sure, what's your email?" Certificate of Insurance, sent from the agent, showing $1M+ liability and current dates.

Walk away: A photo of paperwork from their phone, "we're totally covered, don't worry," or any delay past a day. This single question eliminates half the field.

6. "What's your guarantee, in writing?"

Pro answer: Specific terms — e.g., a soft wash regrowth guarantee with a timeframe (ours is 1 year, written on the quote).

Walk away: "You'll love it or we'll make it right" with nothing on paper.

7. "Who's actually doing the work?"

Pro answer: The owner or named, trained employees. In a trade this young, you're often hiring the person, not the brand.

Caution: Subcontracted crews the estimator has never met.

8. "Can I see local before/afters and reviews?"

Pro answer: Google profile with reviews they don't control, photo gallery of local work.

Walk away: Stock photos, no Google presence, or only testimonials on their own site.

The Quote-Quality Questions

9. "Is the quote written, and what exactly does it include?"

Pro answer: Written scope: surfaces, methods per surface, protections, exclusions, total. (Public pricing is even better — ours is a calculator anyone can use.)

Walk away: A number in a text message with no scope.

10. "Why is your price higher/lower than the other quotes?"

Pro answer: A specific, comfortable explanation — equipment, insurance, guarantee, method. Pros know their numbers. (Calibrate with the 2026 local price guide.)

Walk away: Pressure tactics — "this price is only good today."

11. "What happens if something gets damaged?"

Pro answer: A process: documentation, insurance claim, direct repair. They've thought about it because they're accountable for it.

Walk away: "Nothing's ever been damaged." Everyone who works on houses long enough has a story; pros have a process.

12. "Do you use hot water for concrete?"

Pro answer: Yes, with a surface cleaner — heat is what releases oil and winter salt; the surface cleaner prevents wand striping.

Caution: Cold-water-only is a rental-grade setup. Fine for some jobs; know what you're buying.

Quote Red Flags at a Glance

Red flag	What it usually means
Price far below local range	No insurance, no guarantee, or pressure-on-everything
Door-to-door "in the neighborhood" special	Classic storm-chaser pattern; no accountability next month
Cash only / large deposit upfront	For residential washing, full payment should follow completed work
"We can do it right now"	Real operators are scheduled out, especially May–August
No physical address or service area listed	Hard to find later, by design

Put us through all 12.

Call and ask every question on this list — we wrote it because we like how we score. Guardsman-founded, $1M insured, COI on request, 1-year written guarantee.

📞 218-576-8610

Realtors, HOAs, and property managers: feel free to share or link this checklist with clients — no attribution needed, though a link is appreciated. Related: 2026 Price Guide · The PSI Chart · Soft Wash vs. Pressure Wash