I'll explain what I'm guided by using Bricklink besides my gut and experience. I look at the stock figures (of course, many do not sell there, but still). Of course, I also take into account the number of relevant ads in my country. I also pay attention to the sale price, if there is an opportunity to buy Bricklink cheaper or at the lowest price in my country, then at least I will not lose, and if people decide to import to my country, then the price will already be higher and I will be competitive. Well, I will add, in my opinion, a very important indicator, this is the number of goods sold in the last 6 months, it shows the demand and at what price people are willing to buy.
And if we take into account this logic, then we can say that 80039 can be bought.