It should still be under warranty. But if you want to sell it for parts even the lcd by it self is worth more than 100 dollars.
Yeah my 100th post
Congrats on the 100th post. I have a LONG way to go.
On to the point though... you really mean macbook? not like.. an old ibook or something? (not saying you are stupid or don't know your macs but... It seems weird that something that A. should still be under warranty, unless he smashed it himself and B. is clearly worth more then 100 dollars easily just in spare parts would be so easily discarded.
If so though, I'd tell him to get it fixed, but if he really just wants to get rid of it i'd say grab it, transfer it and get it fixed yourself or sell it on ebay for parts. Even broken old powerbooks and ibooks go for over 100 bucks on ebay for parts!
How much does a logic board cost to get replaced?