At this age you should just ask for favorite colors, and then you pick the complimentary covers. Real privacy demand won't happen until about 11 - 13, so right now just concentrate on making it beautiful. If it is pretty and functional, they will love it! Buy furniture pairs so when you do split them up they each have basics. Advice about dividing the room generally is good, but you don't want big sister declaring any territory! There is a crown detail you can do over a bed that includes curtains down on either side - can provide privacy when you sit up in your own bed - consider this as they get a little older and won't pull it down while hijinxing. If it is beautiful and the textiles are in a color they love (or two colors that work together, like pink and lavender on a spring green or taupe wall &/or turquoise and spring green on a buttercream yellow wall ) - then they will see that they can also be different people who are harmonious together. At 7, she is old enough to pick a great color, but don't ask the 5 year old - her taste is changing daily - just surprise her with something all her own that works with sister's pick. I like the look when people select soft goods that match except for color and find one great print accent pillow that ties colors together for both beds. Stay with neutrals on furniture - you can paint out different stuff so it is tied together with pale gray paint. Think mostly about function - Add shelves and cubbies that hold baskets for stuff - stuff changes but they always have it. If you have room, give them each a desk as they approach 5th grade.

Teal? Just a thought sometimes I think it's smart to match or atleast go with the curtains you'd see in the window

Thanks for all the great ideas everyone and sorry I didn't explain the polycarbonate a bit better :) This is along the lines of what we'll be using... http://www.psp.co.nz/building-brands/corrugated-sheeting/suntuf-polycarbonate The area is an absolute sun trap and we're hoping to use it as an extension to our living space, especially on rainy days! I've just sent my husband out to get a few pots of different stains for is to try - darkest brown (cedar) and a lighter brown (rustic oak) both by Cabots + the black we already have. Hopefully we can decide between one of those! I probably should have mentioned we will have black aluminium pool fencing running along the top of the second retaining wall - so the real question is do we keep everything black (pool fencing, horizontal fence, retaining walls and pergola) or do we go with a dark (or even light) brown for the pergola and retaining walls.... We just keep going around in circles at the moment. Decisions, decisions! Thanks again :)

Sorry I am so late coming to your site - you are an inspiration to all, homeowners and advisers alike. For your planting advice, I suggest you call Merrifield Garden Center to see if they will come out your way. They currently have wonderful garden centers in Merrifield and Fairfax (both in Fairfax County) and a new one in Gainesville, but they may come further south to wherever you reside. (www.MerrifieldGardenCenter.com) Even if they don't send designers to your area, they are worth a trip to see their huge selection for a day of pleasure and inspiration, or to pick up some plants. Most of my clients are in the Fairfax and greater Washington area, but I am currently living out west below Front Royal, VA on the Shenandoah mountainside - wonderful views. cascio.offsite@gmail.com