Which company is reliable to buy a house and refund the deposit?

It was sold to Guangzhou in September, and a deposit of 654.38 million yuan was paid before deciding to look at the house. When I got home, I found there were many problems in the house. I asked them for a refund. I called them three times, and they couldn't return it because of my breach of contract. Then I'll sue them. I feel cheated. I don't have much time to spend with them every day. I consulted several deposit refund companies in Baidu, and I felt that what Shenzhen Dingcheng Business Company said made me feel more at ease. He said that he would not give money in the early stage, and he would pay the labor fee after the money was transferred to my account (he also said that the company stipulated that the retired Commissioner could not invite customers to dinner, but he could report it). Later, he entrusted them to help me with it. They came directly to my apartment and we signed an agreement. Went to the developer twice. They discussed it 1 1 day, then went through the formalities and signed the application for bank card account. I lost some money myself, but I am still very grateful to their company for safeguarding the legitimate rights and interests of our people. I hope to get your money back.