I sell a fair bit on ebay, a lot of comics [mispent youth] which buyers are particularly fussy over condition.
Only problem I had was selling a 7 inch Widescreen incar tft monitor. Nifty bit of kit bloke bought it the whinged that there was no TV tuner and he specifically wanted one for a portable tv.
My reply - which should be the same for the rabbit hutch - is that they bought an item exactly as described in the auction and it's tough sh!t if it doesn't fit the purpose that they expected it for because they have 7 days - or whatever - to ask any questions. And besides, as a private seller you're not subject to ANY rules and regulations with regards to trading standards etc.
So tell her to jog on and do one.