The Upgrade Shop in Pannam Town is run by Sam and located next door to the Item Shop. Mag can upgrade his Cyframe and Cyframe parts here for a fee of 1000.
Sam lives here with his daughter, Patty. The shop seems to bring in quite a bit of money, as Sam is able to afford importing a pet dog for Patty. A back room is visible but not accessible. Items in a glass case and a chair can be seen through the window.