I haggled when I took my grandson, then aged 17, to Malta a couple of years ago but his technique was far better. His mum collects ornamental elephants and he saw a large brass one he wanted to buy for her on the Sunday flea-market in Valletta. The chap wanted LM7 for it (about £11). I offered him LM5 and, though he didn't look happy, he agreed. Peter looked in his wallet and said he hadn't got that much with him and he had really wanted it for his mother but never mind. He looked so downcast and miserable about it the chap said, OK, he could have it for LM3.50. Done - he got the elephant. Peter, later, told me he actually had LM40 on him but he thought it was worth a try. I learned a lot from that.
