It's going to depend on the extent of what they need to do. I asked 3 irrigation contractors last fall how much it would be to add 1 run of poly with 5 heads - about 180' long, connecting to an existing (no longer needed) valve, all in an unobstructed straight line on an empty part of my yard where I didn't think that I had good enough coverage. First quote was $1200. Second quote was $685, and the third quote was $550. I've done irrigation systems myself in the past, and the last estimate was fair, and event the second one wasn't total out-of-line up here...
I'm in a different part of the country, in heavy clay soil, so take this with a grain of salt. I know that if I had to repair a few zones of my irrigation it would be pretty easy to get to $1k-$2k. The contractors up here hesitate to do up-front pricing on things like repair, because they don't know how long it will take. Most of them want to quote it as an hourly rate...I'm in the middle of this struggle right now...
