The most affordable bocce ball sets typically cost around $30 to $50 brand new, but you can probably get a used bocce ball set for less. Note, generally for most sets, you get what you pay for. If you're just looking to get started playing bocce ball or are working on a budget, perhaps start with something cheaper and as you get better or have a bigger budget, maybe then buy a more expensive set.
Mid-range bocce ball sets will set you back around $60 to $90 depending on the brand, material, and quality. These sets typically have plastic filling with an outer resin coating.
Finally, higher quality sets will likely cost around $100 with some premium sets or custom sets going for hundreds of dollars. Generally these come with the highest quality of material and are for the most serious or avid players of bocce ball.