Advice on legal stance of parties

On Monday morning, Susan places an advertisement in the Moonway Gazette which read “For sale - brand new i-pod for $550.00”. Beckett sees the advertisement and immediately rings Susan and tells her, “$550.00 is too much; would you be prepared to accept $300.00?”
Susan replies saying, ‘I was hoping to get the amount advertised’ and before Susan could say ‘but I accept your offer’, the line goes dead and the parties could not establish any further contact.
On Tuesday, Beckett posts a letter with a cheque for $300.00 but unfortunately owing to a postal strike, delivery of the letter is delayed.
That same day, Pitbull sends a fax to Susan offering $500.00 for the i-pod.Susan immediately responds by fax agreeing to sell the i-pod to Pitbull but unfortunately Pitbull is unable to decipher the fax as the message was in Susan’s handwriting and illegible.
Susan hears no further news from Beckett or Pitbull. Two days later Susan is at lunch with her sister Megan, who offers to buy the i-pod for $200.00. Reluctantly Susan agrees to sell it to Megan for that price. That afternoon, Susan receives Beckett’s letter and the cheque for $300.00.
Susan tells Beckett what has happened. Beckett is so upset by not getting the i-pod that she seeks psychological counselling which costs her $250.

What is the legal stance for the parties involved?