When i took over this location about 12 years ago, it was closed, had garbage piled up. Half the vacuums did not work, only 2
changers and only 1 worked for single dollars only, 80 (literaly) burned out light bulbs. Took a few years to build up volume. In bay bill acceptors and credit cards, Dualers, bonus time, Suoerbay are relatively low cost and decent ROI upgrades.
Yes, If you have the demographics and competitive environment there is some money to be made in SS. If you don't take care of it failure is certain just as it is with a tunnel.