Start with size and shape
Square footage matters, but shape matters too. Curves, borders, multiple zones, and transitions can add labor and material complexity.
Base preparation is not optional
Excavation, compaction, aggregate depth, and edge restraint affect how the patio performs. Weak base prep is where many patio problems start. In Kentucky's freeze-thaw cycles, a deep, heavily compacted base is mandatory.
Drainage can change the scope
If water currently moves toward the house or sits in the yard, grading or drainage work may need to happen before the patio is installed. You should never build a patio that traps water against your foundation.