Some installers might provide you with such detailed information without having to ask, some might not. You just have to ask! This is your system, so if you want to see the mapped out plan, just ask. It will be useful for you to have a copy of or handwritten list of the parts (including model numbers) they are using. Later down the road, if you need to replace anything, you will want to know how old the product is, model number, warranty information, etc. If you can get a copy of the map, that would be wonderful for you later down the road. If you ever need to dig in your yard or do landscaping, you will want to know where everything is (pipes, heads, WIRES) so that no damage comes to your system. This kind of map will also come in handy if you ever sell your house, and need to pass the system along to someone else. A lot of customers never see or obtain a map for thier personal records, but it would be beneficial for you.

Some minor common issues you are going to run into are broken sprinkler heads, a stuck open valve, a valve leak, timer issues, etc. Most of these things you can easily fix yourself without having to pay your contractor to come back out and fix it (can be pricey). Most manufacturers provide customer service on these products when you run into a problem. In order for them to help you find replacement parts or troubleshoot, they will want to know the model of the product. You may also want to learn the PSI range in your yard. Knowing your water pressure's strength (PSI) will allow you to choose new kinds of nozzles and parts for your system if you ever need.

Another important thing you will want to know is where the main water shut off for the yard is. There will be a water shut off for your house and another for your yard. In the event of emergency, you will want to know where that is so you can avoid flooding.

Moreover, as a homeowner, you will want to research how a system works if you don't already know. The more you know about your system, the easier it will be for you to perform minor fixes and troubleshoot when a problem does arise. Rainbird has a really good learning center at the link below, as well as Sprinkler Warehouse's "Sprinkler School."

http://www.rainbird.com/homeowner/education/

http://www.sprinklerwarehouse.com/Sprinkler-School-Irrigation-Tutorials-s/5712.htm

I appreciate the detailed answer. Unfortunately, various time constraints prevented us from doing much shopping around. In retrospect, if we had more time, it might have been better to first find an irrigation company and then ask them to recommend a landscaper, as I get the sense that the typical landscape company (owner plus manual laborers) isn't the sort who likes doing the sort of graph that the web sites recommend.

It came out ok, with the biggest problem being two spray heads that overlap, causing a section to be overwatered. I may adjust them down myself, but I'm not sure there's anything better because of the curve of that section. There's another area where my preference would be an edge-shaped sprayer instead of the rotor, because I really don't feel like watering my neighbor's lawn, but I think I'd have to replace the body to do that.

But the rear lawn, which had been full of weeds (morning glory, thistle, and the usual suspects) is looking great!

If you know the model or want to show us a picture of the heads that are overlapping, perhaps we can provide a solution.

They're Hunter PGPs. But I think I'd have to get a decent drawing of the area for it to make sense.

A picture of the situation would be best. Are you able to upload a picture as they are running?