1) Find a design firm whose Reviews mention they're reasonably priced. Then compare different firms, if you find one without a fancy showroom (aka high overhead), you'll probably find a more reasonable price for the same brand of fabric, and same quality workmanship.
2) Go with outside mount drapes, instead of a panel on each side. If you do tiny inverted pleats, the drapes can often still cover the entire window, when you close them at night.
"AFTER" our linen drapes are outside mount only,
to allow room for colorful artwork
3) If you fabric is a high end designer brand, which often equates to very expensive - consider using it for the contrast top, with a more reasonably priced fabric on the lower 70% (as per below):
4) If you don't need functioning drapes, (if they're really just for looks), you can often get buy with one width per panel as long as you use a very thick lining, or don't pleat the drapes, or if you have very little wall space beside the window anyway. Often people love this "lighter" look, as opposed to the formal look of several widths of fabric.
Do you have ideas of your own for keeping custom drape prices reasonable? We'd love to hear your thoughts, just click the word "comment" below.