Wow, that IS priceless. I agree with all the comments. I once read on here that you could charge by the square foot. such as a 55 x 75 = 4125 divided by 144 (12x12) = 28.6.
$15 x 28.6 = 429.68
$20 x 28.6 = 572.90.
etc.
Sounds like a lot, but this piece is PRICELESS!
Good Luck