This new glider window has been updated with clean design, smooth operation, auto-locking hardware, and low handle placement for easy use. Moreover, special hardware allows the sash to be removed so homeowners may clean it from inside the home. The aluminum-clad product comes in 18 exterior colors and seven interior wood species. Cost: from $800. Marvin Windows and Doors. 888-537-7828. www.marvin.com.