Worse comes to worse the orange vest moto guys on the corner would take 40 baht to ride you up to the market, I'm sure. At least take you close enough to walk the rest of the way. Don't forget to do the Kwai market a little bit before the night market area. Come to think of it, if they won't accept 40 baht to the night market maybe to the Kwai market, visit that flea market then walk on up to the night market. Have fun, I actually enjoy the used/2nd hand market a lot.