Based on the provided data, we can observe that the coin in question has had a starting price in the current auction of 18 euros and is in a conservation grade of 70 (MBC-). Additionally, it has been auctioned in the past on several occasions, with varying starting and estimated prices.

The average closing price in previous auctions has been 164.21 euros, with an average starting price of 112.65 euros. The coin has been sold in 14 out of the 17 previous auctions.

Taking into consideration the previous prices of the coin, its current conservation grade, and the fact that it has sold in the majority of previous auctions, we could estimate a maximum purchase price of around 200-250 euros for this coin in the current auction. It is important to note that the final price may vary depending on the demand at the auction and other factors that may influence buyers' decisions.