I'd look for water damage (it's bad on plywood but worse on partical board), lifting/separation on the ply as an indication of prolonged water exposure. Check all seams for "gaps" from weight buckling or the stand being moved while the tank still on the stand. Check the slide to make sure it's not jacked (if it is it's a cheap fix) hindges, too are easy fix.
All in all the stand looks clean (but the white wash has to go if it were mine) and for 30 bucks it's a good price.
All in all the stand looks clean (but the white wash has to go if it were mine) and for 30 bucks it's a good price.