I like doing the Restuarant Wow cause you can get lots of money in the mean time

I just get a super high level poke, TRIPLE battle rotation and faint all three pokes in 1-2 turns with Rock Slide or any other AOE attack. (if they don't use protect). Almost all Pokes can learn Protect so you can teach protect to the low level poke to keep 'em from fainting. If you do use lucky egg + trade bonus, Audino is in one battle and with Lucky Egg + Trade + LV3 XP boost, killing Audino alone gives 23000 XP XD (great for leveling pokes for lv 91+ Pickup to get leftovers)