Inside a Knotworth report: a used-sailboat true-cost example
The headline: three ways this plays out
One wide range hides where uncertainty lives, so the report splits it into scenarios - each states what would have to be true. The verdict tests the conservative one against your ceiling.
The condition read: every status carries its evidence
Around 30 systems each get a status backed by the exact quote that earned it, labeled with where the evidence came from. The crucial status is "not mentioned" - silence is never treated as "done", and an undocumented recollection renders as claimed done, never verified.
The true-cost table: every line is a range with its assumption
Purchase, work, transaction costs and contingency add up to the true-cost band. Each line states its assumption, and any line can be replaced by a real quote from a rigger or yard - your figure then beats ours everywhere, including in the verdict. The ranges come from the published cost methodology.
| Line item | Range | Assumption |
|---|---|---|
| Purchase | ||
| Asking price | $13,000 | |
| Cost-to-sail | ||
| engine | $0 – $14,400 | condition not stated; 3,100 hrs on the meter is within diesel life - rebuild-level reserve until service records confirm (labor ×1.2 for work in US) - CONFLICT: listing shows 180 hrs, seller says 3,100; costed on the higher figure until the meter is verified |
| sails (genoa) | $525 – $1,925 | genoa: original (43 yrs) - past the ~10-yr window; budget from partial to full replacement, survey decides (≈35% of the system band) |
| sails (main) | $600 – $2,200 | main: replaced 2015 - 11 yrs ago, past the ~10-yr window: age-based reserve, not a confirmed defect; check condition at viewing and let the survey decide (≈40% of the system band) |
| sails (other sails) | $0 – $1,375 | other sails: not mentioned - ask the seller; range spans unknown-to-replacement (≈25% of the system band) |
| autopilot | $800 | seller-reported quote $800 - unverified; confirm with the shop, or enter your own figure |
| bottom antifoul | $0 – $1,080 | replaced 2024 - 2 yrs ago, approaching the ~2-yr window: small reserve for condition, not a replacement (labor ×1.2 for work in US) |
| running rigging | $0 – $3,000 | not mentioned - ask the seller; range spans unknown-to-replacement (labor ×1.2 for work in US) |
| ground tackle | $0 – $2,000 | not mentioned - ask the seller; range spans unknown-to-replacement |
| Transaction | ||
| survey | $750 – $1,050 | pre-purchase survey ~$25–35/ft × 30 ft |
| haul out | $300 – $495 | haul-out for survey ~$10–16.5/ft × 30 ft |
| sales use tax | $943 – $1,300 | CA 7.25–10% by county - no cap - due at registration; an out-of-state purchase usually owes USE tax at your registration state instead. Verify current rate and local add-ons |
| insurance yr1 | $98 – $195 | first-year insurance ~0.75–1.5% of value; offshore/liveaboard higher, may require a recent rig + survey |
| registration | $750 – $1,200 | USCG documentation ~$700 + state registration $50–500 |
| Contingency (20%) | $2,600 | post-survey surprises on a boat this age |
| True cost, all-in | $20,365 – $46,620 | |
- Confirmed work (defects, stated quotes, your figures)$800
- Age-based reserves (replaced or original, past or near the window)$1,125 – $5,205 · ±$4,080
- Unknowns (not mentioned - seller questions)$0 – $20,775 · ±$20,775
- Transaction costs (tax, survey, haul-out, registration)$2,840 – $4,240 · ±$1,400
- Contingency$2,600
- engine: up to $14,400 - seller answer or service record for the engine.
- running rigging: up to $3,000 - seller answer or service record for the running rigging.
- ground tackle: up to $2,000 - seller answer or service record for the ground tackle.
- sails (main): up to $1,600 - condition of the main (sails) at viewing, then the surveyor's view.
- sails (genoa): up to $1,400 - condition of the genoa (sails) at viewing, then the surveyor's view.
Most of the width is the unknowns, not confirmed work: the engine's true hours are contested and several systems were never mentioned. Confirmed work is a single line. That is the honest shape of an old, thinly documented listing - and exactly what the seller questions are for.
The seller loop: ranked questions out, evidence back
The highest-value unanswered questions became a short seller message, ranked by their potential cost and decision impact - never more than seven, with the rest held for the next round. When the reply lands, each statement becomes a tracked claim and the report recomputes.
The verdict and the negotiation evidence
The report ends with a plain verdict and an evidence-classed case: a confirmed defect is CONFIRMED leverage, an aging component is AGE-BASED, an unverified recollection must be documented before it counts - and unknowns never enter the case at all.
| Issue | Evidence | Est. cost | Class |
|---|---|---|---|
| sails (main) | Seller states: “The main is from 2015” | $600–$2,200 | AGE-BASED |
| sails (genoa) | Seller states: “genoa original” | $525–$1,925 | AGE-BASED |
| autopilot | Seller states: “The autopilot is confirmed not working — a local shop quoted me $800 to replace the drive unit.” | $800 (seller-reported quote, to confirm) | CONFIRMED |
That last part matters at the dock: the factual trigger for every line comes from the listing or the seller's own words. Knotworth then applies a visible, editable regional cost range - and if the case still rests on anything unverified, the copy button warns you before you send it.
Paste the listing URL. The pre-check is free, and the full report costs one payment for the whole seller loop.
Questions about the sample report
Is this a real boat?+
Yes - a real public YachtWorld listing for a 1983 Catalina 30, run through the actual product pipeline. The seller's reply is illustrative (we don't publish anyone's private correspondence), but every status, range and verdict on this page was computed by the same engine that runs your report - this page is regenerated from the pipeline, not written by hand.
Why ranges instead of one number?+
Because one number would be false precision. A re-rig quote varies by yard, region and what the rigger finds aloft. Every Knotworth line is a low-high band with its assumption stated, and any line can be replaced by a real quote, which then beats our estimate everywhere. How the bands are built is documented on the methodology page.
What happens when the seller answers?+
You paste the reply into the report. Each statement becomes an evidence-backed claim: explicit answers close questions, recollections stay flagged as unverified, contradictions stay visible, and the cost range and verdict recompute. In this example the reply closed the rigging, bottom and engine-history questions and cut the worst case by tens of thousands.
What if the report says walk away?+
Then it says so plainly, with the reasons listed. It is advice, not a block: the unlock stays yours, you can keep asking questions, and an explicit proceed-anyway path exists because the decision is always the buyer's.
Can I export the report?+
Yes. The full report, including the condition read, cost table and negotiation evidence, exports to PDF (your browser's print dialog opens - choose “Save as PDF”), so you can bring it to the dock, to your partner or to the broker.