The most basic and most restrictive answer is that feats like Intensify Spell-like Ability and Quicken Spell-like Ability can't be used during magic item creation: On Magic Item Creation, in part, says, "Using metamagic feats, a caster can place spells in items at a higher level than normal." Since feats that modify spell-like abilities aren't metamagic feats, they can't be used to place spells in items at a higher level than normal.
If a GM wants to shut down this line of inquiry cold then that's that. However, this GM would likely allow creatures the possess one or more feats that exactly mirror one or more metamagic feats to contribute a modified spell to the creation of a magic item at the normal increased price according to the corresponding metamagic feat. For example, this GM would likely allow a creature that possesses the feat Intensify Spell-like Ability to contribute an intensified spell to a magic item, but the magic item's creator would see that spell's spell level increased by +1 (and have to pay a correspondingly increased price) just as if a spell had been modified by the feat Intensified Spell.