Introducing The King County Price Index
We gave our pricing engine a name. Here's what it actually is, and why we're publishing our prices for anyone to see.
Every Prolific estimate — the 90-second range on /estimate, the 3-tier proposal you get from the survey, every proposal we send — has always come from the same place: a pricing engine we built by cross-referencing real completed King County jobs against trade-specific cost data, updated continuously instead of once a year. It never had a name. It just quietly did the work.
As of this week it has one: The King County Price Index. Not because a name changes what the numbers say — it doesn't, the math is identical today to what it was last month — but because "trust our secret formula" isn't actually trustworthy, and a named, explainable system is easier to hold accountable. Including by us.
What it actually is
It's a live table of price ranges — low, mid, high — for the trades King County homeowners hire most: roofing, siding, flooring, electrical, plumbing, HVAC, fencing, and more. Each range is built from multiple independent sources cross-checked against each other, then anchored back to real completed Prolific jobs where we have them.
You can read the full breakdown at /how-pricing-works, or skip straight to the numbers: we publish 15 real ranges, refreshed live, at /price-report. It's free, no sales call attached.
We found our own mistake writing this
In the process of picking which 15 line items to publish, we found a bad data point in our own system: a decking line item was pricing at roughly $983 per square foot instead of the correct ~$46 — a single outlier source had gotten scaled wrong. We caught it, fixed it, and re-verified the number before anything went out. We're telling you this not to bury it, but because a pricing engine nobody ever checks is exactly how contractors end up quoting nonsense with a straight face. Publishing our numbers in public is part of what keeps us checking.
Why this matters more than the name
A named, explainable pricing system is a promise: every number on our site has to survive being looked at. Not "trust us," but "here's the range, here's roughly why, go check a competitor's quote against it if you want." That's a stricter standard than most contractors hold themselves to, and it's the one we're choosing.
If you want to see what your own project would run, the instant range takes 90 seconds and asks for nothing. The full 3-tier proposal takes about 5 minutes and comes back within a day.