Your Jeep should be ready to roll when they're done, everything torqued, lubed, sealed, etc. Generally you get new ring and pinion, ring bolts, pinion bearings, carrier bearings, shims, crush washer, gear oil and pinion nut with a gear install. If you want new axle bearings or seals, you'll have to specify that.
Dont forget about proper break in and I always change the diff fluid after just a few hundred miles so I can check for metal and also to get rid of the break in oil.
price depends on your location. Around here its between 200-250 per axle.