Bob Toh advertised his Honda Civic car for sale at $100,000 cash. Gerald came to accept the offer, but told Bob he could only pay $50,000 cash and promised to pay the remaining $50,000 in five installments. Bob told him he would only sell it to a buyer who could pay the entire amount upfront. Gerald said he would try to raise the money and left.

Shortly after, Henry came to view the car, and told Bob that if he (Henry) hears no more from Bob by the next day, he will consider the car as his for $60,000. Bob thought this to be ridiculous and simply remained silent as he watched Henry leave.

Later that the evening, James came to view the car and told Bob that $100,000 was "rather expensive". He asked if Bob would accept $90,000 in cash. Bob promptly rejected this. A short while later, James called Bob to tell him that he would pay the $100,000 in cash for the car and he would come by in two days to complete the transaction. Bob said nothing and hung up the phone.

The next day, Kenny came to view the car and after some discussion, agreed to Bob's price of $100,000. Bob then sold the Honda Civic car to Kenny for $100,000 in cash.

Gerald, Henry and James each believe they have a legally binding contract with Bob over the sale of the car, and as such are now contemplating legal action against Bob for "breach of contract".

Required: Advise the parties of their legal positions under the law of contract.