I put an ad on Craigslist looking for free glass, patio doors, old windows, fish aquariums, flat glass, mirrors, etc. to make hot beds in my garden. I struck gold today I got 25 free aluminum windows from a double wide trailer home. All I need to do now is buy about 20 pressure treated 2x4 boards to frame a green house then put the windows on with screws. I have enough windows to build it 27 ft long by 6 ft wide or about 14" x 12". This will be great for growing a winter garden and also growing my own plants from seeds in the spring. I am going to put it together with screws so if I move I can take it apart and take it with me. I have a wall fan and thermostate all I need is 2 Louves. All the windows open so I can let out the heat in summer. I hope this inspires someone else to put an ad on craigslist too.