Basically, yes- as a collector if the added items are of value to you, The asking price is good, over the low ball price of someone who wants it for replacing something in use and couldn't care less about the box, and might even consider ditching it.
Since boxes tend to go for $30-$40 by themselves, I'd figure that $90 with the rest representing the computer in the $50-$60 range is about right.
As a buyer, sure, peck at it and see what you can get away with. But if there's more than one of you, you've got to gamble on getting it or not.