Based on the data provided, we can observe that the coin has had an average auction closing price of 99.51 euros in previous auctions. Additionally, the condition of the coin on this occasion is 75 (VF).

Considering that the condition of the coin is 75 (VF) and that the average auction closing price in previous auctions has been 99.51 euros, we could estimate a maximum purchase price of around 110 euros. This is because the condition of the coin is not excellent, but it is also not very low, so a price close to the previous auction closing average would be reasonable.

Therefore, an estimated maximum purchase price for this coin in the next auction could be around 110 euros.