I have a 2009 Rhino 700 with 8500 kilometers on it and 530 hours. In the time I have owned it the only things I have broken so far are :
Lost the lug nuts/studs on the right front wheel. Not sure why but was carrying some spare studs/lug nuts. 30 Mins to fix and back on trail.
I have broken both back axles on two separate rides. Was able to drive back to truck.
Have never had a belt failure but am on my third belt as a maintenance item I have changed. I always have one at the truck/camper. I inspect it at least once every year.
Relays have never let me down but a spare would be a good idea.
Fuses as well as tools,tape,tug strap, clevis's,straps ,flashlight,wire, zap straps, oil,etc.
You will have to build an emergency kit yourself that works with the Rhino.
Tire repair kit (lots of plugs)with pump an essential.
Extra gas for long trips. Go pro or equivalent to film while riding.
You will always need something you don't have.
Be safe and have fun.