I asked the consultant about the cost, and I was not in a hurry to ask how to reply.

Maybe not now. Leave your phone number.

Thank you for your reply. Your price fully meets my psychological expectation, but I may not need it now. Is it convenient for you to leave me a phone number? I'll call you then.

In this way, I can reply to him politely, and then I can give myself a buffer time to let him know that I want to contact.