Yacht valuation methodology for marine surveyors
A practical methodology for arriving at defensible market valuations on small yachts — comparables, condition adjustments, and how to document your reasoning.
Insurance and finance valuations are a steady line of revenue for working surveyors — quicker than full condition surveys, repeatable, and high-margin. The catch is that a valuation is only as defensible as the reasoning behind it. An underwriter who questions a £180,000 figure wants to see the comparables, the condition adjustments, and the market context. Here's the methodology that holds up.
The three-step approach
Every defensible yacht valuation follows the same structure:
1. Establish the comparable base — what similar vessels are selling for, not asking 2. Adjust for condition — what makes this specific vessel different from the comparables 3. Document the reasoning — so anyone reading the report can trace the figure
Skip any step and you have an opinion, not a valuation.
Step 1: Building the comparable set
A "comparable" isn't just any boat of the same make and model. It needs to share:
- Year of build (±3 years)
- Engine type and hours (or sail wardrobe condition for sailing yachts)
- Geographic market (a yacht in Palma sells for different money than one in Hamble)
- Sale status: closed sales only, not current listings
The mistake most surveyors make is using YachtWorld asking prices as the comparable. Asking prices are aspirational; closed sales are the truth. Use three to five closed sales from the last 12 months in the same market.
Where to find closed sale data:
- Boat broker contacts — local brokers will share if you ask politely
- YachtFocus, BoatTrader sold listings where available
- Auction results for the lower end of the market
- Insurance industry data if you have access via underwriters
Step 2: Condition adjustments
Once you have a comparable base, adjust for what makes this specific vessel different. Standard adjustments, expressed as % of base value:
| Factor | Typical adjustment | |---|---| | Engine hours significantly above average | −5% to −15% | | Engine recently rebuilt or replaced | +5% to +10% | | New rigging within 5 years | +3% to +5% | | Major osmosis treatment with warranty | +2% to +5% | | Updated electronics package | +3% to +8% | | Recent interior refit | +5% to +15% | | Outstanding deferred maintenance | −10% to −25% | | Damage history without full repair documentation | −15% to −30% |
These are starting points, not a formula. The valuation skill is knowing when an updated electronics package adds 3% or 8%.
Step 3: Documenting the reasoning
The report section that protects you in a dispute looks like this:
> Comparable analysis > Three closed sales of comparable 2014–2017 Beneteau Oceanis 41s in NW European markets within > the last 12 months: > - 2015, Solent, sold March 2026: £145,000 > - 2016, La Rochelle, sold November 2025: €168,000 (£142,400 at sale-date FX) > - 2014, Lymington, sold August 2025: £138,500 > > Mean closed sale value: £141,966. > > Adjustments for subject vessel > +3% for new standing rigging (2024) > +4% for upgraded electronics package (B&G H5000, 2023) > −2% for above-average engine hours (2,840 vs. fleet median ~2,000) > Net adjustment: +5%. > > Market value assessment: £149,000
That paragraph is what an underwriter wants. Numbers, sources, adjustments, conclusion. No underwriter has ever pushed back on a valuation written like that.
Where AI fits
AI valuation tools have got genuinely useful in the last 12 months. They're particularly good at:
- Aggregating closed-sale data from multiple sources
- Surfacing comparables a human might miss
- Producing a first-pass adjusted figure for you to refine
What they're not good at: making the condition adjustments. That's where your judgement on this specific vessel — the things you saw on the boat — has to override the model.
evalo's AI valuation engine generates the comparable base and a suggested adjusted figure with full sourcing, then leaves the condition-call to you. The report exports with all the comparable data documented automatically. It's a 20-minute valuation instead of a 2-hour one — and the documentation trail is stronger than most surveyors produce manually.
The valuation that loses you the client
Vague. Round numbers. No comparables. "In my professional opinion the value is £150,000."
That's not a valuation, it's a guess. Defensible valuations show the working.