Previous Subie owner here (03 WRX, 04 Impreza, 03 Outback). I've been looking for an older one (2004-2013) for the last 6 months. The amount of people that don't know or don't disclose leaking differentials, leaking transmissions, and head-gasket issues (despite claiming they've been "fixed") is staggering.

With one car I inspected, me and two other buyers came to see it at the same time; I think the seller orchestrated that intentionally. Well too bad for him, I inspected underneath and it was a leaking mess from every section. To which I quickly pointed out to the other buyers. We all walked away lol.

Of course you can have these issues with newer models also, but they're so prevalent with the older ones.