I do not own a LV bag yet, but have really admired the Trevi bag, (pic below). I just have a few questions.... 1. What do the initials PM and/or GM after a number of the LV bags mean? 2. Is the Trevi bag heavy, i.e Paddington, a number of the MJ bags? 3. How much is the retail price of the PM vs. the GM? 4. How is the availability of these bags, and where can you purchase besides the LV boutiques? 5. Does anyone have the dimensions of the PM vs. the GM size? 6. What is the interior material made of? Thank you so much for any help you can give!!!!