This was a mate of mines outhouse, it had a perspex roof so no one could see them. It did just the job, until he got raided. For 40 plants he got a £40 fine. Damn lucky
Trouble was, when they left he said 'Fuck you, I'm gonna keep growing them' so they did him next year as well. Only a small fine again. There was a police training school about 15 miles away, so i think they used his place as atraining ground.