This piece is gorgeous! But i do see some inconsistencies that would lower the price.
The hair on the feet is flowing to the left, which is in tune with the horse trotting towards the right.
But then the mane and tail are going to the right. It makes no sense in that retrospect.
I usually price my pieces at a 5k SB and leave the auction open ended and it just lands where it lands.
If you are looking for a specific AB, i think 30k would be a good price point for this piece. If all the hair flowed the same direction, i think you could probably get 55-60k