ἢν δέ τις καὶ ἔμπορος βούληται ἕπεσθαι πωλεῖν τι βουλόμενος, τῶν μὲν προειρημένων ἡμερῶν τὰ ἐπιτήδεια ἔχειν ἤν τι πωλῶν ἁλίσκηται, πάντων στερήσεται
τῶν μὲν προειρημένων ἡμερῶν τὰ ἐπιτήδεια ἔχειν during the days for having provisions. Gen temporis and inf defining substantive.