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A straight run of n panels needs n + 1 posts, because every section needs a post at each end and neighboring sections share one. Corners, ends, and both sides of a gate need their own posts, and gate posts usually go deeper or heavier since they carry a swinging load. Standard pre-built panels span 8 ft; 6 ft spacing costs more in posts and concrete but sags less over time.

Allow 4 ft for the gate, leaving 116 ft of fence line. At 8 ft per section that is 14.5, rounded up to 15 panels, and 15 + 1 + 1 = 17 posts once the gate post is counted. At two 50 lb bags of concrete per post that is 34 bags — usually the heaviest single item in the order, and the reason fence projects get underestimated.

Bury a third of the total post length, never less than 2 ft, and always below the local frost line in cold climates — frost heave lifts shallow posts and racks a whole run within a couple of winters. Dig the hole about three times the post width, add gravel at the base for drainage, and crown the concrete above grade so water sheds away from the wood. Let it cure 24–48 hours before hanging panels.

String a line between the end posts and mark every hole along it before you dig; moving a mark is easy, moving a set post is not. Take up leftover slack by shortening the last section rather than spreading an odd inch across every panel. Call the utility-marking service first — it's free, takes a few days, and is legally required in most of the U.S. before any digging.

On a slope you either step the panels, keeping each one level with a triangular gap beneath, or rack them to follow the grade, which only works with fencing built for it. Beyond panels, posts, and concrete, the order needs post caps, rails or brackets, gate hardware, and exterior-rated fasteners — hot-dipped galvanized or stainless, since ordinary screws bleed rust streaks down a new fence within a season.