Level 40 is less important because players don't need to level anymore and levels before 30 also because it's rather easy to prepare such creatures myself.
And items: typically weapons, shields, armor and helmets have only enhancement bonuses and other magic properties on them are rare while other accessories are generally rarer to obtain and can have other magic properties.
When it comes to how good these enhancements and properties are, at this level range they have typically required level shown in the toolkit about 5 levels lower than a character likely to use them. So a level 30 melee character will likely have a weapon like Longsword +10 or something like this.