UGG question 10 points?

Kay, so I found a pair of UGGs off of eBay for 35 dollars. The problem is that my mom just bought me two pairs of bailey buttons for 150 dollars each. I dont know if she'd be up to buying me another pair cause she doesnt like used ones. how should i tell her that I want another one. my grandma is willing to pay for it but were going through tough times. no ugg hating please