Based on the provided data, we can observe that the coin in question has had an average auction price of 100.1 euros in previous auctions. Additionally, its condition has been described as "75 (VF)."

Considering that the coin will be auctioned in the upcoming days with a starting price of 25 euros and a historical average starting price of 44.88 euros, we can estimate a maximum purchase price based on the previous data.

Given that the average auction price has been 100.1 euros and the condition of the coin is 75 (VF), we could consider an estimated maximum purchase price around 90-110 euros, taking into account the condition and previous auction prices.

Therefore, my estimation of the maximum purchase price for this coin in the next auction would be around 90-110 euros.