I've only played 4th edition of Shadowrun but I imagine these rules apply all the same. Its kinda like Paranoia, except you don't try to kill your buddy as much, and theres magic.
If you don't see any technological defenses, theres probably all sorts of magical defenses. If you don't see either, its probably a trap.
Corps won't get mad at you if you steal there assets. There multi billion nuyen corporations. They don't care if you steal several thousand nuyen worth of stuff on a run. They might even hire you if you do a good enough job. But never ever kill a mage. A seasoned Mage is a probably several million nuyen
investment thats not easy to replace. Plus the mage's buddies are probably also mages.
Remember to tape everything, and edit yourself out of any tapes you find yourself on.
The new guy you bring along, whose replacing the old guy, who your buddy vouches for as "cool" will invariably flip the fuck out and fuck everyone over.