Precious - what is precious? A photo on the mantle? An heirloom? What is the worth of a thing?
As much as what one would pay.

in the sight of the LORD - God sees all things. This word "LORD" is Jehovah. When God is your redeemer is when he is your personal acquaintance Jehovah

the death of his saints - who is a saint?
Only those who are his children in a covenant relationship