Please help me with this question:

Coursework Question Salma wanted to sell her house and advertised it in the local newspaper on Monday for 400,000. Eshan saw the advertisement and rang Salma to make an appointment to see the house. During the He liked the house but asked Salma whether she would repair the roof before the purchase was completed. On Thursday morning, Eshan received a letter from Salma offering the house to him for 380,000 saying that he had until noon on Friday to think about it. On Friday morning, Eshan emailed Salma to inform her that he would buy the house for the said price. Eshan and Salma agreed on a deposit of 200,000 to be paid and the balance of 180,000 to be paid in 45 days upon completion of roof repairs. Salma contracted with Quick Property Repairs Ltd to repair the roof for 5,000 to be completed within one month. However, the workmen from Quick Property Repairs Ltd discovered that the rear wall of the garage was too weak to sustain the roof repairs. They requested an extra 4,000 to hire machinery to support the wall during the repairs; otherwise, they could not complete the repairs within one month in order for Eshan to complete the purchase of the house. Salma was very unhappy but felt that the work needed to be done and reluctantly agreed to pay the extra 4,000 to complete the repairs. However, once the work was completed, she refused to pay the extra 4,000 and insisted that she would only pay 5,000 as that was the originally agreed price. Eshan inspected the repaired roof but was not happy with the quality of repairs. He refused to complete the purchase of the house and requested his deposit back from Salma. (a) Advise Salma and Eshan whether they have a valid contract. (b) Advise Quick Property Repairs Ltd whether it is entitled to the extra 4,000. (c) Based on the case law discussed in class, advise Salma and Eshan whether either of them is in breach of contract and if yes, what are the remedies available to the other party