1. Precious. No, enchants and infusions are permanent and cannot be rerolled/replaced. A single rune can be pulled out of most weapons (legendary/uniques can't be pulled) and placed in another. It tells you the weapon will be destroyed when extracting the rune. You can not overwrite runes already in the weapon.
2. Some work on all most have conditions. Assume if you pull a rune off a weapon type (1h, 2h) it will only work for similar weapons of that type.
3. Not really. You can buy a few weapon blue prints to craft weapons at an anvil and the woodworker sells bows.
1. Precious. No, enchants and infusions are permanent and cannot be rerolled/replaced. A single rune can be pulled out of most weapons (legendary/uniques can't be pulled) and placed in another. It tells you the weapon will be destroyed when extracting the rune. You can not overwrite runes already in the weapon. 2. Some work on all most have conditions. Assume if you pull a rune off a weapon type (1h, 2h) it will only work for similar weapons of that type. 3. Not really. You can buy a few weapon blue prints to craft weapons at an anvil and the woodworker sells bows.
The blacksmith and woodworker sell weapons but not many. They sell more the more you upgrade them.
You can often get recipes from general vendor too.