How much does it cost to install a sprinkler system at my house?

As most irrigation system are very different from one another, you will see below of what you can expect for an irrigation system to be installed and how it isn't a straight across the board quote for every site.

This is what is going to change your project costs the most.  All sites are different in the layout and these items below will dictate the costs of your irrigation system.

Equipment: Equipment access can speed up the process for installing irrigation so if your irrigation needs to be installed in the backyard of a house that doesn't have access for a trencher, labor will increase due to more labor hours that will be required.  Also, the labor for backfilling and leveling out irrigation trenches for pipe and heads will need more manual labor as well.  A lot of new homes are installed real close to property boundaries with one gate access on the side of the house.  That side of the house typically has a 12" step to a door or an air conditioning unit that makes it difficult for even a lawn mower to pass through.

Rocks: If you irrigation system needs to be weaved in and out of rocks, the cost will also increase as many cuts and additional excavation will be required.  Rock hammering may also be needed if there is no path around.

Hillsides:  Hillsides will also increase the price because of increased labor and modifications to the irrigation system hydraulics to overcome gravity and friction limitations.  

Existing landscape:  Many times we are called after the fact that the homeowner has installed a new lawn to their landscape, hoping to get an irrigation system installed.  In order to protect the freshly installed investment of sod, the irrigation system would have to be "surgically" installed to prevent from damaging or wasting the money invested in the new lawn.  Great care will need to be used when compacting trenches, setting heads and leveling out the soil for the lawn to be laid back down to look as if we were never there.

Water:  You may be supplied by a private well, community well, municipality, private water company, or surface irrigation water.  All of these water suppliers allow a certain amount of water and great care will need to be taken to determine how much water is available for your irrigation system.    A private water well can yield around 5-10 gallons of water per minute, where a private water company can produce 15-20 gallons.  Water availability will dictate the size of each zone.  More water can mean less zones because the zone can cover more area.

Surface irrigation water (from an irrigation canal) will also need to have a in irrigation pump installed.  An irrigation pump will allow you to transfer the water from an irrigation pond in to the irrigation system and pressurize the water.  

All irrigation systems need to be protected with some sort of backflow prevention as required by Oregon State Law.  https://www.oregon.gov/oha/PH/HEALTHYENVIRONMENTS/DRINKINGWATER/Pages/acr.aspx

Spray zones are great for those small areas or even oddly shaped areas.  With distances of 4' - 15' between sprinklers, you can pretty much irrigate any odd shaped area like entry way beds or car strip areas.  Spray heads help keep the water on landscape instead of undesired areas if installed correctly.  

Rotor zones are great for irrigation large areas that have more dimensional.  Think of a park or a football field.  The more dimensional an area is, the better option it is to use Rotors

Controllers can offer you many different features.  Some are just an automation tool to turn the water on and off, while others can sense the weather and make adjustments automatically to reduce damage or over watering to your landscape.  

To determine which controller you need will also be dependent on how many zones you have in your irrigation system.  The more zones your system has, the more expensive your controller will be.  Most controllers start with a base of 4 stations available.  Many can be expandable up to 22 or even 48 zones.  

Drip systems can range in price greatly due to what the actual needs are.  If you are installing drip to flower pots or using drip to irrigate a whole landscape the labor and materials will range greatly.