«بَاعَ بِشَرْطِ الْخِيَارِ إِلَى ثَلَاثَةِ أَيَّامٍ»
He made a sale with an option lasting to three days.
An option permits the relevant party to affirm or undo the transaction within its stipulated period. Interpretation of the terminal period depends on how the expression limits that right.
This is not equivalent to purchasing land “up to a wall.” One is a temporal qualification of a legal option; the other identifies a physical boundary.