Every five years I know this because mine is also due.
To make it a bit easier on my pocket I have bought the service parts this month and will have the service done next month.
I got all the parts from Cardiff Jeep as I got not to bad a discount.
I've still to buy the oil but I get that from Costco as it's a lot cheaper.
This car is very expensive to service although as you have already said a cambelt change would have cost a lot what our cars dont need.