Based on the provided data, we can observe that the coin in question had an opening price in the current auction of 12 euros, with a conservation grade of 70 (MBC-). Additionally, it has been auctioned in the past six times, with an average starting price of 32.33 euros and an average closing price of 39.5 euros.

When analyzing the previous prices of this coin, we can see that in the last auction (auction date: "2022-04-28"), the starting price was 12 euros, the estimated price was 20 euros, and the closing price was 19 euros, with a conservation grade of 70 (MBC-).

Considering these data and the history of previous prices, as well as the current conservation of the coin, we could estimate a maximum purchase price around 25-30 euros. It is important to note that this is just an estimate and the final price may vary depending on factors such as demand at the auction and buyer interest.