Remedies for Breach of Contract: Adam's Case

Adam agreed to buy 1925 Rolls Royce from Edwin, a dealer in vintage cars. They entered into a contract for the purchase of the car at an agreed price of $500 000. Edwin subsequently refused to go through with the contract having heard on the grapevine that there was an Arabian Sheik on the lookout for one who was prepared to pay up to $700 000 for the rare car. Advice adam with respect to what remedies are available to him as a result of the breach of contract by Edwin. Would your advice be different if the motor vehicle was a late model Mercedes Benz? (to be included at least 5 case studies, which must not be from US)