I would start with the high-end suggestions you've received, Eddie. And don't forget to charge for the pillow shams too. Remember, you can always come down in price, but you can't go back up when you find she was going to give you a check for $2000!
If it's still available, see my posting of 8/28/10 of a Lone Star I bartered for a landscape plan; I think I really got burned. (But still wish I'd bought the extra border fabric for the area under the pillows.)
You're an artist ..... a designer ..... and you do beautiful work. Don't sell yourself short!