the first 1000 ruppes are to repair the bridge. then they ask for 2000 to open the shop. however their is a glitch. if you save and then go back to the main menu and load up that save, they will only ask for 200 ruppes
or if you deliver the springwater to the goron, you get a peice of heart and they open up the shop for only 200 ruppees.
*shrugs*
its only 2000 when you havn't done that sidequest i believe.