A house of cards is insubstantial. A house of cards has absolutely no integrity. A house of cards is a fleeting thing.
He is looking for something and he can not recall what it is. It may be a feeling, that is what draws Bob here, it might be an item but unless it is holding my walls and rails together he won’t be finding it here. All the tools and cars and people have been changed.
Did you know dust is almost entirely human skin that is shed daily? Kind of gross. Really gross. Without humans wondering around, cooking, showering, playing, napping, I don’t really need all that much attention.