According to a poll we did of coffee shop owners that have successfully run a coffee shop for at least a year, 94.6% used an espresso machine with at least two groups. Of the 5.4% that used a single group machine, the majority used a large single group machine with 220 volt connection. Most suggested that they were planning on getting a two group soon or wished they had gotten a two group machine. There was only one coffee shop owner that used a 15 amp single group machine and that was in a small town coffee shop that did about 40 drinks per day and the owner suggested that they wished they had a two group machine. At Espresso Outlet we highly recommend that you start your business the right way and start out the right way with a full size machine with at least 2 group heads and a 220 volt connection.