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

1. Current Condition: The coin has a condition rating of 95 (EF+), indicating that it is in very good shape. This generally translates to a higher price compared to coins in lower conditions.

2. Auction History:
- The average hammer price for this coin in the past has been 104.46 euros.
- In previous auctions, hammer prices have varied significantly, ranging from 15 euros to 260 euros, depending on the condition and other factors.

3. Starting Price: The current starting price is 90 euros, which may influence the final price depending on demand.

4. Price Trends: In the most recent auction (2022), a coin with the same condition was auctioned with a starting price of 110 euros, although the final hammer price is unknown. However, this suggests that there is interest in high-condition coins.

5. Comparison with Previous Prices: Looking at previous hammer prices, the highest recorded price was 260 euros, although that was for a coin with unspecified condition.

Taking all these factors into account, an estimated maximum purchase price for the coin in question could be in the range of 150 to 200 euros, given its condition and the historical interest in similar coins. This is based on the average hammer price and the price trend in previous auctions.

Therefore, an estimated maximum purchase price could be 200 euros.