Known issue. Just practice good organization... toss out stuff you don't really need, etc etc (ie don't hold on to leveling whites, minimize the amount of dungeon gear you keep). For ingredients... don't hold on to anything that you might need someday. In fact, don't even keep stuff that you think you might need in a month if it costs less than 20k or so. Only keep what you're currently using in recipes.

Some day we may get better inventory.