Trade Me has been inundated with scammers recently taking over people accounts and selling fake products pilfered from overseas classifieds.
I'd be very wary of the forward growth curve of the Trade Me platform. The discounted and free selling promotions are increasingly offered as a way of coaxing sellers back. There is still huge uasage but i suspect once FB decides to improve their marketplace platform it will take (more) huge chunks away from the used sellers market on Trade Me.