Greenhouse Brainstorming

[GREENDREAMIN]

-So, i am looking to build a greenhouse 10ft by 15-20ft in my yard in the middle of suburbia and am prefferably looking for something cheap and opaque, that wont fall down.
Last year i buitl one from scrap wood lying about. it was 5feet wide by 7 feet long, 6ft 6in high. i only put 3 large plants in the right half, and got a half p per plant. so this year, im gonna go a lil bigger.......

I want to spend 300 for the greenhouse, or i might as well build one.
I have come up with 2 options. one is the shelter logic 10x20x8 white greenhouse that looks like a canopy and claims a light transmission rate of 70%.
I have been trying to find out if anyone knows if that amount of light transmission is enough to grow dense buds? the greenhouse looks like a canopy shelter for a car or something.... im worried that it wont transmit enough light................HELP?

 

[RandM999]

Well, what I am doing:
I found a metal carport frame ( frame only ) on craigslist for $100.00 and am planing on using this as the base for my structure. It measures around 11 ft. x 20 ft. and 8 ft high.
I will be covering it with the thickest poly that I can find. I think Home Depot has 20X100 rolls for around a hundred bucks. I won't be doing a greenhouse ( no power to the site ) but will be making a hothouse and rain cover out of it. Sometime down the road, when I can afford to, I will run power so as to run lights, heat and fans, then I will have a real greenhouse.
I probebly paid too much for the frame, but I was in a hurry and wanted to get going on this project. I imagine that with a little looking around one might even get the frames for free from people who just want to make their carport go away. If the canopy is ratty or damaged most people would find it easier and cheaper to just give the old one away and get a new one rather than try and fix them. Again, try craigslist for what you need.
I've just started on this so I have no pictures or plans, as I kind of make stuff up as I go along ( Oklahoma Engineering