Based on the data provided, we can observe that the coin in question has had starting prices ranging from 9 euros to 250 euros in previous auctions. The average starting price of past auctions has been 45.75 euros, while the average final price has been 61.87 euros.

Considering that the current condition of the coin is 30 (BC+), and taking into account the previous prices of similar auctions as well as the condition value, we can estimate a maximum purchase price around 100 euros.

It is important to note that the final auction price may vary depending on factors such as demand at the time of the auction, competition from other bidders, and specific interest in the coin in question.