El Mariachi is one of the lowest budget films ever to get wide international release. Although exact budget information is not readily available, the film’s creator Robert Rodriguez claims it was in the area of USD $7,000.
When examining what appears on the final screen for this dollar-value, you must remember that Rodriguez dumped his negative straight to 3/4 inch video and edited from there. He did not pay for a 16mm print of the picture, nor make use of any film editing facilities or equipment. When El Mariachi was picked up by Columbia, the studio paid for the prints, the negative matching, the blow-ups, sound remix, the subtitles, and the credits.
Considering the amount of time that was spent on readying the film for theatrical release, and several Columbia-induced blunders during the process, the final film probably cost an additional $200,000 – $300,000 to put on screen (maybe more).
You can get more information on the making of this film in Robert Rodriguez’s very entertaining autobiographical account of the production, Rebel without a Crew.