How do you get buried items?

Items are buried in the walls-HM Rock Smash is supposed to make it so you can break into the wall to get it, but it seems that it's easier to have a Pokemon who can levitate or go through walls, like a Ghost type, and use them to get the item. They can pick it up for your team as long as it's not holding anything, and X-Ray specs or a Scanner Orb may help you to find where the items are. It's also been said that a Pokemon with the pickup ability will get things that are buried for you as it changes to the next floor-since they often find items when they get to a new floor, I believe this to be true. A Trawl Orb will get all unclaimed items on a floor, too. A Mobile Orb will let the leader go and attack through walls. PP Maxes? I'm, pretty sure they're aren't any in this game. Sorry!