πρίαμαι περάω note the aorist infinitive is πρίασθαι not πριάσθαι
1.to have a thing sold to one, to buy, purchase, Hom., attic; c. dat. pretii, πρ. κτεάτεσσιν ἑοῖσιν to buy with one's money, Od.; c. gen., πρ. θανάτοιο to purchase by his death, Pind.; πρ. τι ταλάντου Xen.; π. πολλοῦ id=Xen.; metaph., οὐδενὸς λόγου πρίασθαι to buy at no price, Soph.; πρ. τι παρά τινος Hdt.:—πρ. τίμιον τοὔλαιον to buy it dear, Ar.
2.to farm a tax, Xen.