Not really a beware but..

[skanrashke.livejournal.com]

I need advice on what a proper response to this situation would be. A customer came to me, and we agreed on a commission(A full body costume). We agreed on the price, and she has paid her deposit, and I have purchased her materials. I haven't yet begun work on it, but now she has come to me and asked about 'reducing the price' by changing the commission(to a partial). While normally I don't mind doing this, someone else(Her father) paid for this and contacted me about payment and actually paid the money, and I already have moved her commission back(at her behest) to a later date than we had originally agreed. Should I just change the costume to a partial and alter the price, minus the extra for the materials I've already ordered? Should I contact the one responsible for paying about this? This is really just.. an unusual situation(That I wasn't expecting in the first place) that I need advice on.

Thanks in advance.