LA gained $2B in profits total from the 1984 olys. $250 was earned by the loacl host organization led by USC. $1B was earned by TV. The rest was made by the venues, construction, tourism, hotels, rental car, concessions, etc. That's $4.5B in 2012 dollars. They key was 1) LA already had everything built and used by the public, 2) athletes and fans arrived weeks in advance and stayed months afterwards to visit numerous Hollywood tourist sites, beaches, etc. LA didn't have to spend any serious dollars at all.