Sailor standard price seems to be 50 cp per frag . So with discounts offered by events pick the best one for you knowing her price.

What you need to understand is that every event has an discount ( showed explicit or not). But Sailor' s base price is 50 frags. As you see in this Sage Treasure event you can get her for 35 cp at a 30% discount , 40 at 20% and 45 at 10% so all that means one thing. Sailor' s price in game without any discounts is : X - X/10 = 45 ; X - X/5 = 40 ;

X - 3/10 X = 35 ; So doing the math to all of those is a certainty of 50 cp income.