I'm selling my Gas Technician 2 and 3 modules as I've completed the course here in the Greater Toronto Area of Ontario, and no longer have use for the books.
Gas Tech 2 Modules = $150 CAD
Gas Tech 3 Modules = $100 CAD
They are in good condition, important areas are highlighted as I used the books when preparing for my G2 and G3 exams.
Let me know if you're interested.