From the Athletic:
"Villa received more for Malen (a deal worth €27million) than what they spent on his replacement. A high earner at Besiktas, Abraham made a significant financial sacrifice, in the many millions, to clinch this move, waiving money to ensure he could join Villa"
I know they earn shitloads, but you have to tip your hat to that, and the fact he'd told everyone else over here they could do one as he's only coming to us.