EEK! That's an expensive problem.
If no fans spin, then it seems there is something wrong with the power.
My first choice would be to call tech support for whoever sold the computer. The problem with you making any attempt to trouble shoot is that your efforts may void any warranty. Since there is no evidence that it has ever worked, there is a chance that it is suffering from a manufacturing defect (or something minor has come loose). I you mess with it, it may only get more expensive.
If I had the computer, I would open the case an look to see if anything was obvious and then, no matter what, I'd be on the line to tech support. (unless it fell out of the back of your SUV on the way home)