Based on the data provided, we can observe that the coin in question has had a starting price in this auction of 12 euros, with a conservation grade of 30 (BC+). Additionally, it has been auctioned in the past on several occasions, with varying starting and final prices.

The average starting price of this coin in previous auctions has been 43 euros, while the average final price has been 50 euros. As for the conservation grades of coins auctioned in the past, they have ranged from 10 to 70.

Taking into account the previous prices of this coin and its current conservation grade, as well as the fact that it has sold in most of the previous auctions, we could estimate a maximum purchase price around 60-70 euros. It is important to note that this is just an estimate and the final price could vary depending on the demand in the current auction.