Autoloot is fine. Make sure you don't change looting to free for all, just leave it at group loot.

You will see sparkles on the mobs you can loot. On your main you can loot that. for other mobs you will need to check the screens of your other two characters. If there is a sparkle on the mob loot with that character.

This way all your toons will get items they can vendor.

You will struggle with getting money together for spells though with RAF, as you tend to level faster than the money comes in.

After upgrading from trial versions you would be able to trade with your own characters to have a higher level fund them.