Player spawn an object in a clear area

Players seemed to have lately found a way to crash my server by spawning a lot of props inside a map wall or something…

I tried using tracehull and obbmin and max to check if there is a hit and if there is they wont be able to spawn it, thing is it really interrupts the gameplay and sometimes if the prop is too big they cannot spawn it in buildings and etc. My question is, how do I make sure they wont spawn it inside stuff but at the same time make sure it wont interrupt the gameplay too much?

This would still interrupt gameplay a bit but less than not spawning it all: One option would be to let it spawn but ‘ghost’ it. Disable collisions and freeze it in place until it is interacted with. Once a player picks it up and drops it, check if there is enough room to unghost it, otherwise keep it ghosted/frozen.