For newbies, to estimate the cost of any Lego set, simply multiply the number of pieces by ten and then place the decimal where it makes the most sense.
So, a 9,000-piece set should cost around $900.
This has held true for years. If the set one is buying is less than ten cents/piece, it's a huge bargain.
Years ago, probably five decades ago, a local toy store was going out of business. I bought every Lego set I could afford at the time. I calculated the prices to be five cents/piece, literally getting everything for half price.
This 9,000-piece is going for less than $650. My hunch: on Amazon, eBay, elsewhere, we will see this product for more than $1,000 within a few years.
Currently, despite having just been released, it's out of stock.