Start with the design
Describe the privacy you want, the preferred height and the sides of the property to enclose. Ask the installer to identify the lumber species, treatment and finish in the estimate rather than quoting only “wood fence.”
Questions about the build
Ask how the proposed posts and footings suit the ground and fence design. Include gates, corners, changes in grade and existing fence removal in the scope. There is no single post-depth recommendation here; the design and site need an assessment.
Plan for upkeep
Ask for the material manufacturer’s care instructions and a written explanation of what the installer’s warranty covers. Compare staining or finishing requirements, board replacement and hardware maintenance before deciding.