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 coins with a similar condition (95) in the past has been approximately 370 euros (based on auctions from 2020 and 2019).
- In previous auctions, hammer prices for coins with a condition of 95 have varied, with some reaching up to 495 euros.

3. Starting Price and Estimates:
- The current starting price is 200 euros, which is reasonable given the historical hammer price data.
- The average hammer price in the past has been 187.3 euros, suggesting that the final hammer price could be in a similar range.

4. Recent Trends:
- The coin has been auctioned 46 times, of which 39 have been successful sales. This indicates a steady demand.
- The price trend appears to be increasing, especially for coins in good condition.

Based on these factors, an estimated maximum purchase price could be between 400 and 500 euros, considering the high condition and the historical hammer price data that supports this estimate. However, since the starting price is 200 euros, it is likely that the final hammer price will be closer to this upper range, depending on the competition in the auction.

Therefore, a reasonable maximum purchase price could be 450 euros.