It depends entirely on the value of the car. The best and most valuable cars have sold at Gooding or RM Sotheby's - sometimes Bonhams. Their commissions are 10% Buyer's Premium (what you see listed as the price in Sports Car Market, for example) + a smaller fee for the seller (always negotiable). The upper end of the market these days is in the range $250k US. Ironically that is for 280SL Automatics - either Concours restored or VERY low mileage original. Barrett Jackson is a total crapshoot - no reserve and could be a disaster. For strong, upper range cars - $75k - $100k - I would consider Bring a Trailer - 5% commission paid by the buyer, reserve accepted. You can check the SEARCH link on their website and the prices of all the recent sales will come up. You can also click and find the description. If your car is rare - 5 speed, few owners, known history - I would go with a dealer with great exposure. Typically the fee is 5 - 8% of sale price. Ideally you'll find a sophisticated market that appreciates the simplicity of the earlier cars and a manual transmission - therefore a private broker or dealer.
