This applies to any item with only an enhancement bonus, including all non-special weapons and non-special armor / shields.
2) Pick something. I don't recall a formula being used for it. Lion's shield should have its effective caster level in the description; if it does not, then it must be at least 11 (minimum to create any magic item).
So, if i create i item that is in the monster & treasure the caster has to be 3 times the level of the enchentment. If it's armor that has also abilities, it's 3 times the abilities level (or enchentment if bigger).
If it's weapon or miscellaneous weapons that is in the book it's only three times the bonus ?