Also, didn't your cousin inspect the goods before signing the contract? Signing the contract represents your cousin's approval of this house, and now she wants to return it, which is your cousin's reason, so there must be liquidated damages.
Advice to you: Let your cousin consult an intermediary, sharpen his pain and difficulties, and don't lose his temper, because it is your cousin who is wrong. Last resort: you said I don't want this house anyway. You should return the deposit 1000 yuan to me, and put the other 1000 yuan in your place first, and then deduct the agency fee of 1000 yuan when you help me find other suitable housing!