This guide is from psnprofiles.com
Scattered throughout Kamurocho and Sotenbori are vending machines called Dream Machines. These machines will charge either ¥10,000, ¥100,000, or ¥1,000,000 per use, and the item you get is randomized based on how much money is inserted, not on the location of that machine. Only some of the Dream Machines will be activated at any given time, and after using one, you will not be able to use that machine until you wait for a while and then refresh the area (such as by entering a shop). Reloading a save will randomize which Dream Machines are currently activated.
For this trophy, you need to receive a 10-star item from one of these machines. This is only possible on the Dream Machines that charge ¥1,000,000. I would advise you to use these machines whenever you get the chance because they contain useful items you'll need such as slot car parts, crafting materials, and fishing bait, some of which aren't obtainable through any other means. While 10-star items are somewhat rare, so long as you're using the Dream Machines regularly over the course of your playthrough, you should receive one without too much hassle.
The maps below show the locations of each Dream Machine.