Horrendous fuel mileage and spendy tire replacement are the two things that come to mind from me, a long time (22 years) multiple 4 cylinder Subaru Legacy-Legacy Outback owner. The 3.0 H6 in the 2005-2008 Outbacks makes those cars really scoot and cruise nicely with the 5 speed automatic. I'm sure the 3.0 and 3.6 H6 engines share the same small cylinder shaped oil cooler on the side of the engine case that the oil filter screws on to, and they are prone to leak from either the O ring between the cooler and the engine (easy fix), the oil cooler itself (easy fix more money) or the engine case is damaged where the cooler mounts (expensive fix). So look for oil leaks in that area. They are also prone to the cylinder head gasket issues, the water pumps are internal behind a metal cover with 51 bolts (!) driven by the timing chains supported by multiple plastic chain ramps with hydraulic tensioners.......the list goes on. First thing I'd look at is leaks at the oil filter and remove the oil filler cap and look inside the top of the cap itself. Nobody spends the time to clean the inside of the oil filler cap, and if it is dry and grungy, quite possibly crusty, I'd walk.
That being said, I'd let Faye take care of my plugs.
