Is replacing a radiator expensive?

My neighbor is selling his 2003 Honda Civic because it has a broken radiator. He already has another car. He says he can only drive it a few miles before it overheats. I told him I know a mechanic who might be able to fix it. He said he would just give me the car if I can fix the radiator.

If it has been overheated the head gasket is blown, those are very fragile to blowing the gasket and that is why he is giving it away.

This year of Civics are well known for blown head gaskets and cracked blocks. Often times people spend a lot of money on the head gasket repair only to find out that the block is bad. The radiator is probably fine, run fast and far away from this deal.