tommy, i think you need to give more details i.e.
what are you selling engine wise, short block, long block, in take manifold, timing belt, water pump,oil pump etc
i think you need to think about this more!!
second hand scooby engines dont go for much as a brand new 2.5 block from subaru will cost 2k.
and with 100 thousand km on it, it wont be worth much.
fair enough if your going for a mad long block biuld with racing heads and new everything but that will cost you up to ten grand and will give you lots of power 500 + maybe which your gearbox wont take, so take into account 4 grand for a 6 speed or ppg box