I think it is up to agreement between the players.
I would be happy to face an army where anything that was necessary for the army but could not be afforded was over by provided it was an attempt to make the unit playable and not minimum troops with the rest spent on a single killer Lord.
...a bruiser may be purchased in 500 points games even though it is over 25%. It does not however mention what kit may be taken etc.
So taking the Ogres as an example, the cheapest legal (including any necessary upgrades) character as general could be equipped with a more expensive set of items if the cheapest load is awful.
If you cannot discuss it in advance, I suggest taking a list containing the cheapest option possible with no optional equipment as well as your preferred list so that you can still play if your opponent is more strict than me.