Sam Seller and Betty Buyer meet in a bar and after several cocktails Betty agrees to buy Sam's house for $500,000 in cash. Betty gives Sam $10,000 in cash she happens to have in the trunk of her car to seal the deal and agrees to pay the remaining $450,000 in one month's time when she will take possession of house. They don't have any paper so they wrote their agreement on a cocktail napkin and they both signed and dated it. They are both intoxicated so the writing is messy but they are able include the provisions described above. They order one last drink and toast to their transaction because both are happy. Sam believes he got a good price for his house and Betty thinks she got a good deal on a house she has always liked. The next day Betty regrets her decision to buy Sam's house and asks you, her lawyer, whether she can get out of the agreement. What do you think is your strongest and best argument that Sam and Betty's agreement was not a valid and enforceable real estate contract?