Thanks again for the info. I decided to not go the custom route, and I snagged the Magnaflow 15138 kit for a reasonable price. Now to decide if I want to find friends with the jacks, stands, and tools to do it myself, or find a reputable shop to install it.
2012 Ford Focus SE Sedan, Red Candy Metallic Tinted CC, 5 Speed Manual
SE Sport and Winter Packages, 203A Equipment Group, 17" M&P Wheels
K&N 69-3517TS Intake, Magnaflow 15138 Catback Exhaust, WeatherTech 82573 Window Visors, 5% ON-35 Madico Tint