With some, you first install the outer cabinet in the window, then slide in the chassis. Such models required more work to install, but ultimately they fit more securely. Most manufacturers recommend cleaning the air filter every few weeks. Most filters slid out easily. On the basis of our knowledge of the industry, we believe that's still true.
Recommendations Look first at the highest-scoring models of the appropriate size.
And in humid regions, also look for at least a good score for moisture removal.