Based on the data provided, we can observe that the coin in question has had quite variable starting and final prices in previous auctions. The current condition of the coin is estimated at 30 (BC+), indicating that it is not in the best condition, but it is not among the worst either.

The average starting price in previous auctions was 90.09 euros, while the average final price was 176.9 euros. However, in some previous auctions, the final price exceeded the estimated price by a large margin.

Since the coin has been auctioned 11 times in the past and has been sold 10 times, with only one case where it did not sell, we can consider that it has some demand in the collectors' market.

Taking all these factors into consideration, and considering that the current condition is 30 (BC+), we could estimate a maximum purchase price around 150-200 euros. It is important to note that the final price in an auction can vary depending on the demand and competition from other interested buyers.