Just some tidbits on Lyd8ia.
She has thieving skills. Not as good as an actual thief, but she can find and disarm traps and open doors.
She can also do some minor healing by CLW. She's not a magical heavy weight by any means... She has charm person and cure light as her spells and can cast twice a day... plus some useful cantrips.
But, she is a skills monkey with some impressive options, if not great modifiers. It was either con or Int and I went with con... if everyone thinks that the int mod would be better in this case, I can switch them, But she can make any skill roll untrained as if she were trained, so nothing to sneeze at.
On the price question, I'm thinking that the prices were in addition to, Otherwise, it would just be the first enchantment that is difficult and it read like every inchantment would be more difficult. At 3K, +1 is only 1K more, but at +2, it's a non-existant extra for having the better armor. That wouldn't make sense to me.
So, 5K for the first enchantment, 11K for the second, ect... plus the initial material cost of the weapon, as indicated by our illustrious GM.