Assuming we dont go beyond the 12m figure,and going by reports which suggests its a 3 year contract so the investment on him amounts 28.5m in total(5.5m wages * 3).Pretty reasonable if you ask me.
And add the investment on Llorente(0m + 18m in wages) so that amounts to 46.5m euros(excluding bonus clauses) in total on two quality strikers.Less than 50m so thats pretty good business when you look at teams like United for example who've spent 80m euros in total on just a single player in Van Persie who is older than both and likely wont have much resale value.Just an example but ofcourse this all doesnt matter much when success is achieved on the pitch especially when talking about a team with a very high turnover.