Sprinkler systems are pretty straight forward, minus the backflow assembly. However, even with a trencher, there is still quite a bit of digging involved. (You have to hand dig a hole for every head.) If you have like 4 dudes, you can install one in one weekend. Probably save a grand or so by doing it yourself. I used to actually install them for a couple summers but paid to have mine put in. (Bad memories of swinging a pickaxe in 100 degree weather.)