Hello & welcome, have a look at the buying guide that's lurking around, although it's impreza based it applies to all subaru's things to look out for on the foz are mainly head gasket's but I think the 2.0 is fairly bullet proof ot's more the 2.5 (Mr b will confirm at some point I hope)
And check the rear shocks, if it has the self leveling units (sls) and that they are working correctly, easiest way is to park the car on level ground and have a look at the way she sits, if it looks like a dog scraping it's bum on the floor then They will need replacing, don't go to subaru unless you want a giggle or heart attack, they can be replaced for normal shocks and springs at a third of the price subaru will quote for a single sls unit.
Apart from that they are great cars and if your into changing a few bits or dressing the engine bay up 90% of the corresponding years impreza bits will fit
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