On Volvo 96' and newer, the factory alarm system is not easily bypassed. However, if you get a standalone system, that will NOT operate the locks, has all it's own sensors, and power, it should be no problem. I know someone that has installed one on a 99' C70 HPT. He installed a Clifford standalone. He still uses the OE remote to lock and unlock doors, but has a sensor for the hood, the trunk, the doors, glass break sensors, shock sensors, BUT NO engine kill system, because that interferes with the stock alarm system. So yah, his car is pretty sensitive to stealing individual parts, but stealing the entire car is still no more difficult then defeating the lowly oe alarm system.