(i) No arguments
While dealing with this type of customers the salesman must not argue with them. He has to digest the ironical remarks of the customers as he has to sell.
(ii) Concentrating on selling points
The salesman should concentrate on selling points of goods. He should never try to cure them, because their temperament is not curable.
(iii) Praise and smiling face
Instead of getting hot and serious, the sales man of getting hot and serious, the sales man should make a smiling face as it is the best medicine against the bad temperament.