On the Caymans the 987.1 (2005-2008) and 987.2 (2009-2012) had hydraulic steering, but with the redesign in the following 981 generation (2012-2016) they went to an electric steering rack. I believe it was similar with the Boxsters, but I'm not 100% sure. Also, the Boxter launched earlier than the Cayman so I'd imagine that the earlier 986 generation of Boxster also had hydralic steering.
If at all possible (which often it is not), try and find a 987.2...they included some improved aesthetic details (headlights/tailights/stereo etc) and more importantly an engine redesign that did away with the potential IMS bearing and bore scoring issues sometimes seen in the 987.1's. But also keep in mind that the internet would have you believe that these were widespread issues in the generation when in reality I think it was something like 4% of cars that had those problems. It could be scary though because an IMS failure would completely grenade the engine.