Stacey Smith owns a lot in the hills of Pennsylvania and wants to build a house according to a particular set of plans and specifications. She solicits bids from bidding contractors and receives 2 bids: one from Carlton for $260,000 and one from Feldberg for $258,000.One night, while having a drink with friends during happy hour Stacy is telling her friends about her desire to build this home and her uncertainty of the costs associated with the project. Siegel, although laughing with others at the table, had heard Stacey's story and leaned across the table and said, "you are being taken for a ride because you are a lady.If you let me, I will build your house for half of that price, no more than $125,000!"Delighted, Stacy jumps on the offer and says I accept. I will have money for you tomorrow to get started.The next day Siegel shows up at the property and Stacey pays him a $100,000 down payment to cover most of the construction costs One month after beginning construction of the house, Siegel contacts Smith and tells her that because of inflation and a recent price hike for materials, he will not complete the construction unless Smith agrees to pay an extra $150,000. Smith reluctantly agrees to pay the additional sum. 4 months later Smith has an unfortunate accident resulting in her death. Stacy's only son, Tom wants the construction completed.

Is there a valid contract between Stacey & Siegel, enforceable by son Tom? Remember we will discuss capacity, legality, mistake and fraud.