To estimate a maximum purchase price for the coin in question, we can analyze the provided data and consider several factors:

1. Condition: The coin to be auctioned has a condition of 95 (EBC+), which is quite high and suggests that the coin is in very good shape.

2. Previous auction prices:
- In previous auctions, coins with a similar condition (95) have had hammer prices that varied, but generally, the hammer prices have been in a high range. For example, in 2018, a coin with a condition of 95 was sold for 3600 euros and another for 1300 euros (although the latter had a lower starting price).
- In 2023, a coin with a condition of 85 was sold for 2700 euros, indicating that condition has a significant impact on price.

3. Average hammer price: The average hammer price for this particular coin is 3026.25 euros, which can serve as a good indicator of market value.

4. Starting price: The starting price of 1500 euros is relatively low compared to previous hammer prices, suggesting that there could be a good buying opportunity.

5. Auction trends: Given that the coin has sold in all previous occasions and has had a hammer price that exceeds the starting price, it is reasonable to assume that interest in this coin will remain.

Based on these factors, an estimated maximum purchase price could be in the range of 3000 to 3500 euros, considering that the average hammer price is 3026.25 euros and that the condition of the coin is high. This would allow for competitive bidding in the auction without exceeding the market value observed in previous auctions.