About Luck Refiner skills.

Wanna ask this for so long already.
Which skills are needed for Luck refiner specifically for +B-S.. Do I need to max All 3 skills namely: Refine equipment, Mid class refinement and High class refinement? Just wanna ask about this since and cause +B-+S is just a Wait for the coin's decision, 1%.. Cause if not.. Its a save of sp. And can make out from this Luck refiner to be able to play to End game.. Including Boss Hunts.

 

According to mayam L1 refine(for +A/S).but I put mine 5-5-10. Did it before asking.
Im using tec 0-B.