I remembered the truth when you said it. Yes, he can be released for €75 million a year. There are at least 10 teams that will line up to pay this fee. So selling Haaland this year makes every sense. €150 million is a very good fee. I hope Dortmund can sell it this year. For that money they can get a very good striker.
If Dortmund can find a good offer about €150 million, they will sell Haaland immediately because they know Haaland will leave the club and they will have cheaper offer in the next two years.
Unfortunately, with financial sufferings from the pandemic, €150 million is very expensive, even the player is Haaland. Dortmund must announce cheaper transfer price for Haaland. €100 - 120 million is more realistic and feasible price for other clubs to buy Haaland.