Well, to be fair, there are a few more than 4 bolts if you want to do it the easy way. You have to remove the metal piece covering the 2nd cat (which is 4 or 6 bolts) and move that metal bar that crosses over where the pipe bends up towards the downpipe off to the side, which means removing another 2 bolts I think. In all, it should take about an hour, and is very straight forward. Nothing tricky at all.
Just MAKE SURE you let the car cool off for a couple hours at least before even attempting to work on it. That stuff gets really hot and you'll definitely burn yourself if you don't. You can test by spraying cold water onto the surface of the exhaust and seeing if it steams.