Washing things that are washable at a high temperature, like blankets, (sorry can't remember what temp!) and I believe you can get stuff that kills fleas depending on what type of housing you're thinking but I don't know if this is really safe for the rabbit. Sorry not really sure what else but I'd throw away things that can't be cleaned thoroughly as I wouldn't want to risk a re infection. I threw everything away and had to replace it when Beano had ear mites (similar to fleas but live in the ear) as despite thorough cleaning I just couldn't get rid of them and didn't want her to get another infection, but ear mites are different to fleas I presume.