When buying things that have possibilities of ganna chop, cameras, watches, jewelery, luxury products, etc:
Look local.
Speak Singlish.
Establish and maintain eye contact. Sales newbies find it harder to chop someone who look at them in the eye, (sense of guilt in humans), but hardened old timers won't.
Try to speak with stronger, lower pitch, even if your a girl. Lower voice tone projects more authority.
NEVER look nervous. Nervousness is carrothead's number 1 common trait worldwide and its telling sales people come and chop! Maintaining eye contact is one good way to project confidence.
Hold a piece of paper in your hands with the words MS, TK, J316, Lords and CP written boldly in columns against your shop list. It shows that your comparing prices and it will make their 200% quotes ridiculous.
Always ask for net prices. Credit card price is 2% extra, thats the common standard. Once Lords tried to pull 3% on me, lucky I know 2% is the common standard. Lucky Plaza is only lucky for retailers if they find carrots.
Last rule; if a shop appear that they are not interested in selling or serving you, then they do NOT deserve your business, there are MANY other camera shops.