For starters, I wouldn't say that looks very well made. It's all pretty basic stuff. I don't think the camera needed tracking, I think they shot it stationary, then digital zoomed and added in the shakes after all of the effects were finalized. The explosions are just awful and a lot of the colors don't match up with the raw footage.
Plus, they don't properly (or at all) blur things that are placed in the distance, especially in that last shot.
Having that mini-rant out of my system, directorik's estimations are spot on. Those explosions and 3D models are free online. It wouldn't take ME that long to make this, but again, it's pretty basic stuff. I'd attempt to make it look a hell of a lot better, too, even though my track record for CG work has been to just do what I have to for the purpose of my story (I've gotten better at VFX and CGI and would not consider this passable if I were making a video that needed these effects)
It would take a while for renders. It could also take some time looking for well-made models online, most of them are pretty bad (but with how fast some of them are moving, with some good motion blur, you wouldn't even be able to tell)
Most of the hard work in this is just in the sound editing, so in total, it could take 80 hours to make this, and it all depends on what you're paying people per hour.