My twin tower condo in Waikiki was built in 1976.....has no sprinklers.  Hmmmmm.  Anyway, I don't care.  Concreat bunker construction, four fire hoses on every floor, alarm system that will wake up the dead, fire doors on every unit, fire extinguishers in every unit, 24 hour pro active on site security and one fire (extinguished in 20 minutes, no injuries) in 42 years.  Maybe I'll knock a couple grand off at closing for a sprinkler credit but that's it.  Besides, how do you know these 10-20-30-40 year old sprinkler systems work anyway?  You gonna put a match under the sprinkler head in your living room and see if the water starts flying?