Repair keeps you safe
An older fence in a slightly wrong spot is typically a legal nonconforming structure: maintain it, and it stays. Rebuild it from scratch, and it has to be in the right place at today's limits — 7 feet side and rear, 4 feet in the front setback. That asymmetry makes repair-first not just cheaper in Menlo Park but legally simpler. The heights, the corner triangle and what a rebuild reopens are all in the fence rules and permits guide.
Next step
Photograph the worst post at its base and the full run showing any lean, and send them through the form for a repair range before anyone drives out.