Unwashed windows accumulate layers of grime that can build up and block out the sun, causing light-hungry houseplants to turn to TV sets and birthday cakes. Replace sullied windows with today's Groupon: for $345, you get a single-hung Milgard Style Line window and installation from American Home Renewal (up to a $690 value). This Groupon is valid for customers within a 50-mile radius of San Francisco.

American Home Renewal’s team of licensed and bonded renovation experts fortifies residences with energy-efficient windows, siding, and doors, offering a customer-satisfaction guarantee with every portal the company installs. A single-hung Milgard Style Line window gives homeowners the aesthetic benefits of streamlined, maintenance-free vinyl frames as well as reduced energy costs courtesy of dual pane SunCoat Low-E insulating glass. Windows may be ordered to fit up to 100 united inches, and today’s Groupon covers the new window, the removal and disposal of existing windows, installation, and sealing of new windows plus engraved stationery you can use to invite sunbeams to your newly windowed abode.