A bow well taken care of should last many many years.

The cost to replace strings and cables depends on what type of strings and cables you put on it. Myself I would spend the extra $$$ and get Winners Choice or similar top notch set. Mathews make a great bow but they use some of the worst strings and cables out there. You puton a set of Winners choice for around $75.00 + shipping from www.yeoldearcheryshoppe.comI buy most of my Winner's Choice products there they seem to have very good prices.