To estimate a maximum purchase price for the coin in question, let's consider several factors:

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

2. Auction history:
- The average hammer price in previous auctions for coins with a similar condition (95) has been approximately 139.16 euros.
- In the most recent auctions, the hammer price has ranged between 165 and 201 euros, suggesting that there is growing interest in this coin.

3. Starting price: The current starting price is 150 euros, which is slightly higher than the average starting price of 111.74 euros, but it aligns with previous hammer prices.

4. Recent trends: Recent auctions have shown an increase in hammer prices, which could indicate an upward trend in the value of this coin.

Considering these factors, an estimated maximum purchase price could be in the range of 200 to 220 euros, given the growing interest and the condition of the coin. This would allow for competitive bidding in the auction without exceeding the market value observed in previous auctions.