[Jack Simth]

Nah - just Planar Bind two Noble Dijinn or Efreet, and convince them both to grant you the three wishes they can grant to a mortal each day in rapid succession - two regular Planar Bindings (6th) will do, as they both have 10 HD each; granted, there is some uncertainty in that - opposed Charisma checks (Efreet and Noble Dijinn should be running at Char 15, mostly), with modifiers for payment, a save involved in getting each critter into a prepared circle (Efreeti have a will save +9 vs. Planar Binding's 6th level spell DC), and spell resistance (which neither has, and this portion can be eliminated with a Calling Diagram) - but a competent Sorceror could get +5 Inherent to all stats at level 12, with a little work (one engraved circle and three spells per binding - Magic Circle Against the appropriet alignment, Dimensional Anchor, and the Planar Binding spell itself - 10 minutes to scribe a circle (at 12th, with max ranks in Spellcraft, you can take 10 and succeed without any difficulties), 1 round each for Magic Circle Against X and Dimensional Anchor, and 10 minutes to cast Planar Binding itself). An hour's work and a Sorceror with three appropriet spells can have +6 to the stat of his choice ... assuming the Sorceror wins the opposed Charisma checks, and the critters don't make their initial will saves.

No XP expenditure at all....