Cables and housing are easy - just need a cable cutting tool, and use old cables to judge length ($20 online or $35 + labor at lbs)
Cassette - needs special tools (possibly chain whip and possibly splined removal tool and preferably torque wrench) ($20 online and i paid $38 at lbs recently for cheapest they had)
Rings - may need whole crankset - may be able to just do rings. Will most likely need to remove arms (probably just normal crank-puller from square taper bb - definitely want torque wrench) - may want to check and possibly replace bottom bracket when you do this. ($35-100 depending on what you replace with)
Chain - easy with good tool, tedious with crappy tool ($15). lbs may charge $10 to install, which could mostly pay for a nice tool.
The LBS will evaluate wear for you. Just ask 'em straight up how much it will cost to replace stuff.