After Prom House Rentals Conviencing Dad About Senior Prom...?

Conviencing dad about senior prom...? - after prom house rentals

So I need an evening gown! his prom and the dress, what they want is 318 $. its soooooooooooooo pretty and I really, really want, and I know that if I succeed, I have all eyes! omg i can not stop thinking about it! Nevertheless, when I showed my father told me not only intended to spend 50-100 dollars on rent, I want him soup when he charged 100 to pay the remainder (218) might be worth to me? cuz i want it a night you will never forget! So, what should I do?
ps father is at home