On average, the cost of a California IID is about $3.00 per day. Some companies additionally charge around $75-$100 for installation. You may also be required to pay fees for maintenance and calibration of your ignition interlock device. Under California's mandatory IID pilot program law (Vehicle Code 23700 VC), if you can't afford the cost of your mandatory IID, you will only be required to pay a portion of the costs. Finally, the DMV will charge an administrative service fees of $103.