Like you I own a bare aluminum greenhouse and after I got it erected I thought about how much nicer it would look if it was painted. I decided not to paint because I'm at the age where I want to make things where they require less maintenance. Painting once would be a big job but repainting every few years was what made me drop the idea.
If you do paint it be sure you use the special primer for aluminum. Paint don't bond to aluminum very well unless you use the right primer.
I know I would like the looks of mine better if it was painted but just not willing to create something that will need constant maintenance because when it starts to Peel off it will look worse than the bare aluminum does.

I wonder if you could get the frame colour-anodised locally.

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You could get it powder coated the color of your choice but it would cost much more than painting it.

It would cost more than the HFGH...

Posted by: weebus Z8 Sunset 5 WA (My Page) on Thu, May 25, 06 at 11:16
It would cost more than the HFGH...

YEP it sure would.

Thanks, guys. It does seem like it'll be more hassle than it's worth to paint.

Alia