Goalkeepers - cheap or premium?

Some managers will have made up their mind before starting tinkering with their lineups. "David De-Gea it is and a 4.0 GK sub". Others will go for the 4.5 rotation of Fabianski & Foster. But what will really yield the most points in the end? I try to decipher this question by taking the 1.5 you would potentially free up by NOT going for DDG and instead investing it in your D/MF/A.

Looking at the GKs above who all played more than 28 matches there is a clear correlation between cost and Total Points. Doing a simple regression on this gives you y = 28x + k meaning that for every 1 million you spend on a GK you should expect an extra return of 28 points during the course of a season.

Applying the same approach to D/MF/A gives the following overview.

Your money is best spent on goal keeping. However, if you manage to hit the right 4.5 GK and then spend the 1.5 to upgrade your Kolasinac to your Azpilicueta, then do so. I myself will most likely go for a 4.5 GK & invest in heavily in defence.