You can build your own but to be honest it's a lot of hassle when you consider your time unless you are going to build a bigun As 2sheds says try freecyle or Freebay or keep your eye on the small ads section of your local paper, If you havn't got space for a fulsize greenhouse you can always modify the frame of a 2nd hand one and it will be cheaper than building one ( plus most of the accesories will fit OK)

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ntg

Never be afraid to try something new.
Remember that a lone amateur built the Ark.
A large group of professionals built the Titanic

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