Answer:
It doesn't live within a house, nor does it live without. Most will use it when they come in, and again when they go out.
I dig out tiny caves and store gold and silver in them. I also build bridges of silver and make crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs my help. Yet many people are afraid to let me help them.
I am the yellow hem of the sea's blue skirt.
What is it that you must give before you can keep it.
How far will a blind dog walk into a forest?
What did the piece of wood say when he saw the screwdriver and screws approaching?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?