If my own experiences are anything to go by, he is probably pretty fed up with people messaging, and asking "Is this still available?", and "What is your best price".
If I am selling something, I want them to send me a phone number, and when I ring, for them to say, "I will be over tomorrow to view, Is that OK for you?"
Just my take on it. Being an old fashioned type, I like face to face, rather than endless messaging and questions.
Face to face also protects the buyer. If the seller, or the vehicle, are well dodgy, the seller is unlikely to invite you to their house.
Apparently this is the favourite first line of our european cousins, normally put across as best price, not what is yout best price? or are you open to offers,? just best price!
People are to price obsessed these days, cheap cheap and more blody cheap, even the tv adverts are geared this way trying to make out you are a fool for not getting best price all the time.
I kind of think if you are happy with the item and what you paid for it happy days.