This is an illusion. There is no perfect preventative for want, but even if there was it would stand in opposition to the trust in God to which we are called. Trust in God frees us from a need to build a massive buffer against poverty. Part of the cure may be to embrace poverty. We may not become homeless, but we can learn to do with less.
Serious campers try to leave their campsite in the same state they found it.
Ideally, there should be no trace left when they move on. In the same way, try to use less of the world's goods. Live simply, that others may simply live. Once this kind of freedom is practiced, we realize that we don't need that much, anyway. This knowledge, in turn, reduces our fear and builds a kind of strength and confidence.