Alfonso Cuarn was offered the chance to direct this installment in the series, but declined as he would still be working on Harry Potter and the Prisoner of Azkaban (2004). Over 3,000 girls turned up at the auditions for the role of Cho Chang, in London on 7 February 2004. The Dursleys were cut from the film due to time constraints. According to rumors that circulated the Internet, both
Rowan Atkinson and John Malkovich were considered for the role of Lord Voldemort. Both were proven to be untrue; Malkovich is, of course, an American, and doesn't meet the "all-British-cast" requirement. Rumors on the Internet of the a Scottish actor being cast as Viktor Krum were halted when it was announced that, as originally planned by the producers, a Bulgarian would in fact play the part. Perhaps these rumors arose because the Bulgarian was discovered in England and not in Sofia, where there was a casting call for the part of the International Quidditch Champion. Stanislav Yanevski, a Bulgarian student living in London, has been cast in the role. Mike Newell decided against the studio's original idea of adapting the 734 page book into two separate films to be released several months apart, figuring that he could cut enough of the book's bulky subplots to make a workable film. Mike Newell only received $1 million to direct where Chris Columbus recieved $10 million plus a percentage of the gross to direct "
Harry Potter and the Sorceror's Stone (2001)". Philippine actress Heart Evangelista was considered for the role of Cho Chang and Katie Leung eventually beat more than 3,000 girls for the part.
According to Mike Newell, the movie is set to become the most expensive movie ever, with a budget of $308 million. It is around $10 million more than the budget of the entire Lord of the Rings Trilogy, which was nearly $300 million. Currently, the two movies with the largest budgets are Titanic (1997) and Spider Man 2 (2004), both having a budget of $200 million I got it from Veritaserum.com