kate,
how many kids do u have? if u are preg with number 2 or so, then u also need to consider if your number 2 shld take the handsdown from your number 1 because u also need to consider structural rigidity, loose parts, bed bugs, parasitic insects.
of course when people buy 2nd hand, they will check the product before they buy. be it new or 2nd hand items, all items bound to have a risk!