my roommate has a jdm h22 with a spun bearing, he is trying to sell and he would give me a good deal on it. my question is how much work would it be to get it up and running? what normally causes a spun bearing? and any idea of the costs? thanks.

 

you basically need a whole short block,you could reuse that same head

spun bearing=over reving, low oil psi,wrong bearing size after rebuild etc..
more than likely your boy never checked his oil ...

 

to get that engine running again you need to get the crank reground and a whole new set of bearings for the crank and the rods