Hey guys. I'm planning on buying a 2004 lariat f350 from a buddy for $4500 (I think I could get the price down $1000-1500), but the engine is blown. Other than the engine being toast, the truck works fine, and is worth keeping. The truck comes with a used engine as well, currently in his garage. I'm trying to figure out if this could be economical. I want to do this on the cheap, but it needs to be done right too.

First off, (I do not have a lot of mechanical know-how/experience) does anyone have an estimate to get the engines swapped by a mechanic? I would transport the vehicle. Would it be worth it to remove the engine myself and let them put the other used working engine in for me, how much would that cost and how hard is it? I also don't know how to test an engine to see if its worth paying money for to stick under the hood. I'm pretty sure that the engine type, being a newer model f350 engine, doesn't matter. I'm looking for practical info and quotes for cost. Thanks guys.