This camera bag can fit quite a lot - as far as small bags go. i would say its slightly bigger than the Fendi mini By The Way.
This is my current fav bag to carry. Its lightweight and the wide strap is comfortable.
The leather looks and feels quite sturdy, although the front panel with the snake, i believe the black base is printed with the snake, and not a black piece of leather and the snake printed over (if you get what i mean) - so i wonder if the red version would have colour variations between the different pieces of leather.
The red and the black are the same size - although Gucci do make a pouch version of this bag without the strap that is smaller than this.
i dont usually carry much so it can fit quite alot to me.
i can fit all these with a little bit of tetrising with space to space. The photos dont show my phone as im using it to take the photo but i can fit that in there also.
... Sunnies work better in a flat pouch and my key holder is abit larger than "normal" holders and it goes in fine.
i can also replace my card holder with a zippy wallet and still works.