Based on the provided data, we can see that the coin in question has a starting price of 25 euros and is in a conservation grade of 30 (BC+). In the past, it has been auctioned 9 times and sold on all those occasions. The average starting price in previous auctions has been 40.56 euros, while the average final price has been 60.56 euros.

Additionally, data from previous auctions of this same coin have been provided, including starting prices, estimated prices, final prices, and the conservation value at those times.

Given that the coin is in a conservation grade of 30 (BC+), and considering the previous final and estimated prices, as well as the current starting price, we could estimate a maximum purchase price around 70-75 euros. It is important to consider that this is just an estimate and the final price may vary depending on factors such as demand at the auction and buyers' interest at that time.