Playpen climber - Any suggestions?

[Artsand crafts]

I've seen at Safety Superstore something that looks like a mesh that covers cribs (I am not sure if they have something similar for playpens). It is suppose to cover the whole top of it to prevent kids from climbing out.

I cannot wait until a kid is old enough to switch them to cots. I usually do that around 15 months. I do not want to keep holding them when they start to get heavier and playpens use too much space. I do the same with highchairs. I hate them since they use too much playroom space. As soon as they are able to get in and out of child size chairs by themselves I get rid of highchairs.