Can I store stuff at the Goodsprings Schoolhouse?

Solution 1:

In New Vegas, as in Fallout 3, if a container is marked 'respawn' the contents will be overwritten every 3 in-game days with whatever is the default for the container type. This is why it's generally unwise to leave anything you may want to save in a random container.

However all the containers in the Goodsprings Schoolhouse are not marked as respawning containers, so it should be safe to store any excess loot there.

Solution 2:

I personally use the Garbage Dumpster next to the Goodsprings store. Its quick, right next to the Express Mail machine, and I have not had it respawn on me, saves me a walk anywhere, and I can just fast travel to Goodsprings to drop stuff off. I have a crapload of stuff in there.