You might contact Santa Cruz about their recommended settings for that shock/bike (I don't believe there's an archived setup guide on their website, but I really haven't looked for one), they are somewhat bike specific. They do great phone and email in my experience. It's hard to look at a shock or fork and tell if it needs service unless there's something obvious like a leaking oil seal or valve. I'd hope you've already had a chance to inspect the stanchions on the fork and the shaft on the shock to make sure they're not scratched/gouged. Hopefully the last owner has done regular maintenance on them, did you request that info?
If they do need service, your local shop may or may not be able to handle it. There are some places like Push Industries, Dirtlabs, HippieSuspension and others that do service and, sometimes, modifications to customize it for you/your riding (especially Push for Fox shocks).