|Subject: Accomodation near Heathrow|
Years ago our daughter stayed at the Hotel Ibis at Heathrow. The rooms were tiny but so was the price (compared to anything nearby at the time). Start here http://www.ibishotel.com/catalogue/frm_catalogue.asp, type London, click Display all hotels, click OK on next page, etc. You'd have to find out if they have rooms suitable for three.