As a former developer of OpenCart, I've been around from the beginning. I've been making custom extensions and mods for OpenCart for over 7 years. I'm also the original creator of the extremely popular vQmod Modification System
I'm based in Chicago IL, USA but do custom work for customers worldwide. One of my specialties is OpenCart Upgrades. I've done over 400 upgrades and can guarantee data will be 100% safe no matter what version you have and what version you want to upgrade to.