Actually, you don't have to worry, the salesman of the intermediary company is in a hurry. Experienced merchants will communicate with the owners according to your price. It's not like going to the vegetable market. This is business. When your price is basically the same as the selling price of the owner, the intermediary company will go all out to facilitate the transaction.
First of all, you need an intermediary company to communicate with the owner. Secondly, you go out in person and the intermediary company arranges an interview. Don't be too active and indifferent. The intermediary company will fully cooperate with you in bargaining.