£100-£400? I don't think I've ever paid for checked luggage long haul. Even going to Australia most airlines include one 23kg bag. Who is he flying with that its be that much? Megabus air?A checked bag will add another £100-£400 to a flight easily for that distance, just think of the customisable LED Christmas lights he could buy with that.
It's one of them really y'know.
All I can say is, there's no way I'd do f'cking laundry on a holiday (unless I was staying in an AirBnB, which is a concept also out of his price range...)