THE BARATELLI INSTITUTE · Mentoring at Scale
FOR CONSIGNERS, ESTATE EXECUTORS, AND COLLECTORS DECIDING WHERE TO SELL

A $100K hammer = $7K to the seller you might keep, after everyone else gets paid.

Sotheby\'s, Christie\'s, Bonhams, Heritage, RM Sotheby\'s — buyer\'s premium 25-29%, seller\'s commission 5-15% sliding by lot value, insurance, photography, illustration, internet, withdrawal fees. Total friction is typically 25-40% of hammer price. This tool runs the numbers and compares auction to private treaty, dealer, and fractional platform alternatives.

25-29%
Buyer's premium
5-15%
Seller's commission
25-40%
Total round-trip friction
5-10%
Buy-back fee if no sale
YOUR CONSIGNMENT
1
The lot
2
Auction house
3
Premium & commission
4
Other fees & risk
5
Take-rate verdict
STAGE 1 OF 5

The lot

Defaults model a $100K classic car at RM Sotheby\'s — typical mid-tier collector consignment.

Different auction houses specialize. Sotheby\'s/Christie\'s: art, jewelry, watches, wine. RM Sotheby\'s/Mecum/Bonhams: cars. Heritage: coins, comics, memorabilia. Bring a Trailer: cars (online). Choose your category.
Your honest expectation of where the auctioneer\'s gavel will fall — NOT the buyer\'s total payment, NOT the high estimate. The hammer price is what the bidder bid; everything else is added on top or subtracted from.
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Used for net-of-tax calculation. If unknown / inherited at stepped-up basis: enter current hammer estimate (zero gain).
$
Below the reserve, the lot doesn\'t sell. Typically set 70-90% of low estimate. If reserve isn\'t met, lot returns unsold; you may owe BUY-BACK fee (5-10% of low estimate) at most houses.
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Why most consigners are surprised by the take. The headline numbers an auction house promotes are usually buyer\'s premium percentages and "consignment fee structures." What\'s NOT visible until you negotiate the consignment contract: insurance (deducted from gross), photography ($200-1,500 per lot), catalog illustration ($500-3,000 for a full-page color), internet/marketing fees (1-2%), buy-back fees if reserve isn\'t met, withdrawal penalties if you change your mind. Add it all together and the round-trip transaction cost on a typical lot is 25-40% of hammer.
STAGE 2 OF 5

Auction house selection

Major houses have different fee structures. Top-tier (Sotheby\'s, Christie\'s, Phillips) command higher prices but charge more. Boutique / specialty (Heritage, Bring a Trailer) have lower fees but may produce lower hammer prices.

Drives default fee structure. Mid-2026 representative rates; verify current consignment terms before signing.
Live in-person auction = highest visibility, highest fees, traditional 25-29% buyer premium. Online-only = lower fees (often 10-15% buyer premium), wider reach but possibly lower prices. Online + live = hybrid; most major houses offer this now.
Listed seller commission is usually negotiable. Default for $100K-$500K consignment: 8-12%. Above $1M: usually negotiated to 5-8%. For $5M+ "trophy" lots: sometimes ZERO commission (auction house gets only buyer\'s premium). Bring your alternative quotes.
Some auction houses guarantee a minimum price (or arrange a third-party irrevocable bid). If the lot fails to sell or sells below guarantee, the house / IPB pays you the guarantee. In exchange: house keeps a portion of any upside above the guarantee (often 50%) AND charges higher commission. Common for $1M+ trophy lots.
Negotiate everything except the buyer\'s premium. Buyer\'s premium is set by the auction house and bid as part of the announced fee schedule — non-negotiable for sellers. Everything else is negotiable: seller commission (especially $500K+ lots), photography, catalog placement, marketing inclusion, withdrawal penalty, buy-back fee (sometimes waived for valued consigners). Don\'t accept the first contract. For $1M+ lots, get competing bids from 2-3 houses; they\'ll match each other on commission to win the consignment.
STAGE 3 OF 5

Buyer\'s premium & seller\'s commission

The two largest fees. Buyer\'s premium is paid by buyer (effectively a sale tax). Seller\'s commission is deducted from your gross.

Sotheby\'s/Christie\'s 2026: 27% on first $1M, 21% next $5M, 15% above $5M (sliding). Bonhams ~28%. Phillips ~28%. RM Sotheby\'s 12% (cars are lower premium tradition). Mecum 10%. Bring a Trailer 5% (capped). Heritage 25%. Auto-defaults if you select house above; you can override.
%
Sliding scale by lot value. Under $50K: 12-15%. $50K-$500K: 8-12%. $500K-$5M: 5-10%. $5M+: 3-7% or negotiated zero. Cars typically 5-10% (much lower than art). Verify your specific scale.
%
Most houses add 1-3% to buyer\'s premium for online bidders (covers platform costs). Doesn\'t affect seller directly but reduces effective bidder pool willingness to bid up.
%
If you have a guarantee and lot sells ABOVE guarantee: typical 50% of upside goes to house/IPB (you get 50%). Set 0 if no guarantee.
%
STAGE 4 OF 5

Other fees & sale risk

Insurance, photography, illustration, internet — these are deducted from your gross before commission. If the lot doesn\'t sell, you may owe a buy-back fee.

Per-lot photography. Standard catalog photo: $50-300. Studio quality with multiple angles: $300-1,500. Commissioned photographer for major lots: $2,000+.
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Catalog page placement. Quarter page: $500-1,500. Half page: $1,000-3,000. Full page color (premium positioning): $2,000-10,000. Often "free" for high-value lots; charged for everything else.
$
Coverage from consignment to sale (or return if unsold). Typical: 1-2% of low estimate. Some houses include in commission; others charge separately. Ask.
%
Total of: shipping to/from house, additional marketing inclusion (online ads, magazine inclusion), pre-sale restoration if recommended. Variable.
$
Most major-house lots sell (~85-95% sell-through). Lots with aggressive reserves above market estimate: 50-75%. Specialty / off-market lots: 30-60%. If lot doesn\'t sell, buy-back fee applies.
%
If reserve not met. Typical: 5-10% of low estimate. Sometimes negotiated to zero for valued consigners. ALWAYS ASK ABOUT THIS BEFORE SIGNING. Heritage, Bring a Trailer often have lower or zero buy-back fees.
%
The buy-back fee that traps consigners. If your reserve is too high and the lot doesn\'t sell, you owe the buy-back fee (5-10% of low estimate) AND get nothing back. On a $100K low estimate that fails to sell at a too-high $80K reserve, you owe $5-10K of buy-back fee. Plus you have a "burned" lot that\'s harder to consign elsewhere (other auction houses see the failed sale and adjust expectations). The defensive move: set reserves at 70-80% of low estimate, not at full estimate.
STAGE 5 OF 5 · TAKE-RATE VERDICT

Auction take-rate

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Per-lot waterfall (if sells at hammer)

Channel comparison: same lot, different sale paths

Take-rate metrics

Recommendations

PAIRS WITH
Treasure Asset TCO · Estate Planning for Collectibles · Treasure Assets Guide
The TCO Calculator quantifies the carrying cost that put you in this position. Estate Planning for Collectibles handles the 28% federal collectibles tax + related-use rule on the sale or alternative bequest. Subscribe to the library →
TREASURE ASSETS GUIDE

Selling a treasure asset is a decision, not a transaction.

Auction-house selection by category · consignment-contract negotiation playbook · reserve-pricing math · alternative sale paths (private treaty, dealer, fractional platform) · post-sale tax sequencing · the difference between a great sale and a bad one (hint: it\'s NOT the hammer price).

Auction-house fee structures vary and change frequently. Mid-2026 representative rates used; verify current consignment terms before signing. Categories with specialty houses (cars, watches, wine) have very different conventions than fine art. Some houses (RM Sotheby\'s, Mecum, Bring a Trailer for cars; Heritage for memorabilia) have materially lower fee structures than the generalist art houses (Sotheby\'s/Christie\'s/Phillips). The model uses standard sliding-scale conventions but does not separately compute: estate-discount programs, charity-sale variants, restricted-bidder sales, "white glove" sales, or reserve-met-but-still-fails edge cases. This is not legal, tax, or auction-strategy advice.
WANT THE METHODOLOGY BEHIND THIS TOOL?
This calculator is one chapter of Treasure Assets Reference Guide.
The tool gives you the answer. The guide gives you the argument — the case law, the worked examples, the negotiation playbook, the cross-check tables, the exception cases. Read the chapter and you can defend your number to a board, a buyer, an examiner, or a counterparty.
The methodology behind this calculator is in Ch 14 Disposition Planning of the reference guide.
See the Guide → Browse all 22 guides
PROFESSIONAL DISCLAIMER · PLEASE READ

Educational and informational purposes only. This calculator and any output it produces are intended solely for general educational and decision-support purposes. They do not constitute investment, tax, legal, accounting, appraisal, lending, insurance, or any other professional advice, and they do not create a fiduciary, attorney-client, accountant-client, or advisor-client relationship of any kind.

Estimates based on your inputs. All results are estimates derived from the data and assumptions you provide. Tax law, accounting standards, regulations, market conditions, and the specific facts of your situation can materially change the answer. The Baratelli Institute, its affiliates, and any co-branding professional make no warranty of accuracy, completeness, currency, or fitness for any particular purpose, and disclaim all liability for decisions made in reliance on the output.

Consult your own qualified professionals. Before acting on anything calculated here, consult your own attorney, CPA, financial advisor, appraiser, lender, or other qualified professional licensed in your jurisdiction who has reviewed your specific facts and applicable current law. The Baratelli Institute is a publisher of practitioner reference material. It is not a registered investment adviser, broker-dealer, law firm, accounting firm, appraisal firm, or lender.

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