Many suppliers will put dry clean only on their curtains (including the custom made ones) to protect themselves from people mishandling the fabrics and if there's a block out backing on the curtain then this might not be washable. Linen will shrink if you put it into a hot washer or dryer but as Julia has indicated linen is a beautiful fabric to use if you do the right thing by it - if your wanting linen for the block out use a fabric backing rather than a linen that has a coating and make sure that the block out fabric can be separated from your linen fabric (curtain makers will hate it as it's a nightmare double handling, but if you're going to spend a lot of money on linen and for them to be made, it's not unreasonable to request this.

We've just installed roller blinds. We're on acreage so privacy is not an issue. However, we did put block-out blinds in the bedrooms (for sleep purposes) and sunscreen mesh fabric blinds in all other rooms. Re the latter, you can see through them whilst still retaining privacy. They stop 85% of the sun's heat and up to 99% UV. We moved to the northern rivers area of NSW earlier this year so we'll see how we fare in the summer. I suspect the see-through blinds will be down most of the time but because they're almost transparent they don't block the light.

as you said really depends on materials and size but $3000-$4000 should have some basic window coverings installed .... Spotlight has regular generous sales and we're quite happy with their products and services and so much easier to include their installation service as well...but always worth getting some quotes from local suppliers

Grey goes beautifully with navy, adding white also lifts it to another level, a beautiful rug under the bed will tie it all in to create a gorgeous bedroom, your dresser will blend in as you have the blue and white pieces as well. Maybe a beautiful tray with some gorgeous pieces would look wonderful on the dresser.