Based on the data provided, we can observe that the coin in question has had an average starting price of 26.85 euros in previous auctions, with an average closing price of 59.59 euros. The current conservation grade of the coin is 80 (MBC+), indicating that it is in fairly good condition.

When analyzing the previous prices of this coin in past auctions, we can see that it has had a wide price range, from 15 euros to 140 euros. The conservation value has mostly been high, with grades of 75 and 90 in previous auctions.

Given that the coin has been auctioned 7 times in the past and sold in 6 of those instances, we can infer that there is market interest in this coin.

Taking all these factors into consideration, and considering that the coin is in fairly good conservation condition, my estimate for a maximum purchase price would be around 70-80 euros. This range is based on the historical prices from previous auctions and the market interest that this coin has generated.