Considering you’ll break down and reassemble your travel crib multiple times during its life, you want it to be made to last. Quality of materials can be largely gauged by sight and touch. If the crib wobbles when you press the sides, it’s likely not very sturdy. Look for a crib with a strong frame and fabric or mesh sides that pull tight.
It’s also important to pay attention to what’s in the materials used in your travel crib. Flame retardants and other chemicals can be harmful. Look for cribs that meet standards for healthy materials, like OEKO-TEX or GREENGUARD, or otherwise specify that they do not use flame retardants, PVCs, lead, phthalates, formaldehyde or other harmful substances.