Outside of tournament play, proxies (fake cards) are generally permitted. They range from writing the name of the card you want on a much cheaper card all the

Outside of tournament play, proxies (fake cards) are generally permitted. They range from writing the name of the card you want on a much cheaper card all the way to professionally printed cards that weren't printed by Wizards. There are also some very good and still cheap decks. Price is a function of supply and demand, and some decks can take advantage of high-supply low-demand cards (because they only work in a very particular deck). Budget probably is a factor for tournament play. Small differences can be big at that level of play, and proxies aren't allowed.