You do not need a tune up. The car does it on its own more than 100 times a second with the computer.
What you want is... Change spark plugs, oil, filters (Air, Fuel and Oil), check coolant and a bunch of visual inspections that are marked on the Owner's Manual.
Go to the mechanic and ask what they check and what they do. I bet that will be a bunch of visual inspections and some routine maintenance prescribed on your Owner's Manual. The replacement of a Serpentine Belt due to cracking is not a tune up, is the replacement of a defective part.
You can do that yourself.
If not, go to Wal Mart and ask for the Mobil 1 oil change, they inspect and check all the stuff of your car for $45 or so (that is included with the oil change), the oil is good up to $15,000 I change mine about $7,500 or when the car computer tells me, like 2 times a year. They can tell you if you have a cracked drive belt or you fluids are low.
tune up, what the hell are they tuning?