There are too many variables. Is the newbie setting up a road bike, commuter, path bike, MTB, etc? Is newbie willing (and able) to shop for bargains and do a lot of work themselves? Is newbie willing to go used on the bike and or other stuff?
I spent $300+ above the cost of the bike setting up my new commuter (excluding clothes) and already had some of the stuff I needed (and I shopped deals and did everything myself). I have friends who I ride with who bought a bike and a helmet and that was it.