Hi,
1. Set the "Display the quantity field on the product page" option of the HikaShop configuration to "global on listings". It seems that this is not the case looking at your products listing.
2. You can add custom item fields yes. You can create them via the menu Display>Custom fields. And edit your menu item via the menu Display>Content menus and make sure that the option "Display custom item fields" is turned on.
3. No, that can only be done on the product page with a characteristic:
www.hikashop.com/support/support/documen...html#characteristics
4. Then you probably want to remove the "payment" view from your "checkout workflow" option of the HikaShop configuration so that there is no payment method selection on the checkout.
5. Sure but you don't need another extension to do that with HikaShop. As I said, it's possible by default, provided that you set it up properly.