Based on the provided data, the coin in question has a conservation grade of 95 (S/C-), with a starting price in the current auction of 50 euros. It has been auctioned a total of 124 times in the past, being sold in 101 instances and not sold in 23 instances.

The average starting price in previous auctions has been 32.99 euros, while the average final price has been 43.34 euros.

Considering the previous prices of this coin, where the estimated price has ranged between 20 and 100 euros, and taking into account the high conservation grade (95) of the coin, an estimated maximum purchase price of around 90 euros can be considered. This is because the starting price in the current auction is already 50 euros, and the estimated price in previous auctions has reached up to 100 euros.

Therefore, an estimated maximum purchase price for this coin in the current auction could be around 90 euros.