To estimate a maximum purchase price for the coin in question, we will consider several factors:

1. Coin Condition: The coin has a condition rating of 95 (S/C-), indicating that it is in very good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Previous Auction Prices: By looking at the hammer prices of coins with a similar condition (95), we can see that they have reached hammer prices of up to 1400 euros (as in the auction on November 24, 2020) and 1300 euros (in the auction on October 17, 2018).

3. Starting Price and Average Hammer Price: The current starting price is 600 euros, and the average hammer price for this coin in the past is 266.59 euros. However, given the high condition, it is reasonable to expect that the hammer price will be above this average.

4. Market Trends: Since the coin has been auctioned 87 times and has a good sales history (sold 78 times), this suggests that there is consistent interest in this coin, which may increase its value.

5. Estimated Prices in Recent Auctions: In recent auctions, estimated prices for coins of similar condition have been as high as 1500 euros.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 1200 to 1500 euros. This is based on the historical hammer prices for coins of similar condition and the interest in the coin. However, the final price will depend on the competition in the auction and the willingness of other bidders to pay.