Based on the data provided, we can observe that the coin in question has had an average auction closing price of 86.1 euros in previous auctions. Additionally, the current condition of the coin is 70 (VF-).

Considering that the current condition of the coin is relatively good and that the average auction closing price in previous auctions has been 86.1 euros, we could estimate a maximum purchase price around that value or slightly higher, taking into account that the starting price in this auction is 25 euros.

Therefore, an estimated maximum purchase price for this coin in the next auction could be around 90-95 euros. It is important to note that this is just an estimate and the final price could vary depending on demand and other factors in the auction.