Which auction house gets more?

Sort the auction houses by the median price of everything they sell and you get a list of which houses carry the expensive cars. That is not the question. A house that deals in Ferraris and pre-war cars will show a high median because of the cars, and one that sells a lot of everyday modern collectibles will show a low one for the same reason.

The version of the question with an answer is: when two houses sell the same model, do they get the same price for it? That is measurable in this data, because the same 28 models appear across many houses.

For every model and every house with at least 20 sales of it, divide that house's median by the model's overall median. Then take the middle of those ratios across models. The result is how a house's prices compare with the market for the same cars.

The range column is the honest part. A house's ratio is not the same on every model — the spread across models is wide, and often wider than the gap between houses. That means the house effect is real but modest next to the effect of which individual cars the house happens to sell.

One cell in that range is not a market. RM Sotheby's low end of 10% comes from a single day in October 2024, when the house sold a collection of dismantled and project cars: 19 of them fall in the Porsche 912 set at a median of $4,144, against $49,000 for the model overall. They are correctly low prices for what they are — but they describe a salvage sale, not the market for a running car, and a range presented without that caveat would read as though RM sometimes sells a 912 for a tenth of its value.

It cannot tell you what your car would fetch in a different room. The cars at one house are not the cars at another: a model's lots at a specialist marque house skew toward lower-mileage, more original and better-documented examples, and those cars would fetch more anywhere. The ratio above is a description of two inventories, and part of the gap it shows is the inventory rather than the room.

Nor does it account for the buyer's premium, which differs by house and is not part of the hammer price in this data. A house that charges a higher premium can show a lower hammer price and still cost the buyer more.

Where a single model has depth at several houses, the detail is worth looking at directly. Here are four, with each house's median for that model and its count.

Porsche 911 1974-1989

RM Sotheby's: $168,000 on 80 sales (267% of the model median); Gooding & Company: $137,200 on 33 sales (218% of the model median); Broad Arrow: $129,080 on 32 sales (205% of the model median); Bonhams: $71,600 on 56 sales (114% of the model median); Bring a Trailer: $63,500 on 2,732 sales (101% of the model median); PCARMARKET: $50,125 on 250 sales (80% of the model median); Barrett-Jackson: $47,300 on 70 sales (75% of the model median). The model page.

Ford Mustang 1964-1973

Barrett-Jackson: $61,600 on 1,324 sales (149% of the model median); Bonhams: $51,520 on 23 sales (125% of the model median); RM Sotheby's: $46,475 on 68 sales (113% of the model median); ACC: $39,270 on 35 sales (95% of the model median); Mecum: $38,500 on 73 sales (93% of the model median); Bring a Trailer: $36,250 on 2,155 sales (88% of the model median); Autohunter: $29,000 on 133 sales (70% of the model median); Hemmings: $28,550 on 139 sales (69% of the model median); Hagerty: $24,875 on 94 sales (60% of the model median). The model page.

Toyota Land Cruiser FJ40 1958-1984

Bonhams: $59,400 on 21 sales (170% of the model median); RM Sotheby's: $50,600 on 37 sales (145% of the model median); Barrett-Jackson: $39,050 on 199 sales (112% of the model median); Hemmings: $34,750 on 32 sales (99% of the model median); Bring a Trailer: $34,000 on 1,040 sales (97% of the model median). The model page.

Ferrari 355 1994-1999

RM Sotheby's: $114,800 on 23 sales (114% of the model median); Bring a Trailer: $104,000 on 321 sales (103% of the model median); Barrett-Jackson: $69,300 on 23 sales (69% of the model median). The model page.

If you are buying, the useful reading is that the room changes the price less than the car does. A well-documented, original example will do well almost anywhere; a project will struggle almost anywhere. Where the room matters is on the margin, and the margin is where a bid target is decided.

Run a report on the car you are looking at, or start from what each model sells for. The method behind these figures is on the method page.