The actual cost of a lie detector test is truly determined on a number of different factors. Included in these are things like the length of the test, the substance of what is being tested and the location where the testing is done.
Obviously, if the test goes on for a full day as opposed to 2-3 hours, the cost is going to be considerably higher. For instance, if you see a quote for $400 for a lie detector test, that typically is for the lesser range. As the length extends to double the time, the price will increase correspondingly.
When it comes to the subject matter being discussed, obviously a lie detector test in a serious criminal matter is going to cost more than a pre-employment interview. The same rule applies if the test is conducted in a formal lab setting rather than simply in one’s home. All these factors will weigh into the final cost making it important you establish that before proceeding forward!