>>1306076Well, drilling into the outside of the building is a HUGE concern for your landlord. If it is done incorrectly, the entire wall will get water damage and when it needs replaced someone will be super pissed. The best course of action is to talk to your landlord about it. They might have a special contractor they want to use, who can also be the fall guy in a lawsuit.
Now, for your photo, that is a clamp, but for a window sill there are window supports where the hangar actually rests in through the window. Here's one style that is normally used for a porch railing, but there are ones for the window too. Plus....
