irrigation used to be around $75/head. And like everything you get what you pay for. a company near me gets a ton of biz because they undercut their competition by close to half. same price per head, but a lot fewer heads. The goal is to cover head to head. the cheap guy near me, the coverage is not nearly as good. With good water pressure, the heads should reach around 30’. So you want them spaced no more than 30’ apart, the closer the better, which means more heads and more $.
my guess is that your system is going to come in around $5k