Based on the data provided, we can observe that the coin has had an average auction closing price of 78.8 euros in previous auctions. Additionally, the condition of the coin on this occasion is 75 (VF).

Considering that the coin will be auctioned in the coming days with a starting price of 25 euros and has had an average starting price of 53.01 euros in previous auctions, we can estimate that the closing price could be around that range.

Given that the condition of the coin is 75 (VF), and taking into account previous closing prices as well as the average closing price, we could estimate a maximum purchase price around 80-85 euros. This is considering that the coin is in a medium condition of preservation and that the average closing price has been 78.8 euros in previous auctions.