No! For the love of God, OP, don't do it! Don't EVER, EVER buy swords in Chinatown!
Sure, they look nice, but they're all for decorative purposes only. Useless for cutting even cardboard. But if you really want to, just bring 20 or 30 dollars with you. I doubt you even need that much, though...you can always haggle it down to much, much less than what is being offered.
On the other hand, real swords cost much, much more. About 300 dollars and up. These are usually made of 1055 carbon steel, while Chinatown swords are made of low-quality stainless steel. The vendors at Chinatown will of course tell you how sharp and hard their swords are, and maybe even give you a demonstration (unlikely). Don't fall for it.