If your window has no casing but a blind, mini-blind curtain rod brackets are also a good alternative to fixed brackets. On a scale of 1 to 10, I'd give these options 9 or 10.

If your rental has bare windows and you need a rental-friendly DIY that won't jeopardize your deposit ASAP, you'll love this no-drill solution for installing window treatments: peel-and-stick ...