Assuming you top up to get the 8 free chances every day it should cost you 300 for each point. He takes 15 points. 300x15 = 4500 gold
Edit: It doesn't even matter if you top up, you can just get him in 3 days instead of two for the same price.
if you top up for 3 bonus chances you get 8 total a day
each outo win is 60 gold
to go all the way from begining to end is 300 gold
300X15= 4500 gold "theoretically less if you top up daily with gold wheel and 20% rebate"