Those that do delivery into Singapore will need to add on 7% GST (Singapore tax but in RM) and levy (depending on shop's volume, it can range from RM200 to RM350). Adding on all these still make the total cost cheaper than getting in SG. If you drive or even take the bus/train into JB, you can buy the smaller items like LED light bulbs, taps, toilet accessories, house deco. Singaporeans are allowed up to $600 worth of purchase without having the GST slapped on.