A good set of metric tools is the BEST investment you can make on your car ownership, IMO.
Various sockets (10mm, 12, 13, 14, 15, 17, 19, 21, 23), wrenches, screwdrivers, and of course, TORQUE wrench.
Extenisions go a long ways, especially the wobble ended ones. You'll also need an inverse hex...