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

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

2. Starting Price and Previous Prices: The current starting price is 150 euros. In the past, we have seen hammer prices that varied significantly, but there are examples of coins with similar conditions that have sold for significantly higher prices. For instance, at the March 2022 auction, a coin with a condition of 95 was hammered down at 550 euros.

3. Price Trends: The average hammer price for similar coins is 113.75 euros, but this may be influenced by coins with lower conditions. Given that the condition of the coin in question is high, it is reasonable to expect that the hammer price will be above this average.

4. Analysis of Previous Prices: By observing the hammer prices of coins with similar conditions (such as 80-95), we can see that hammer prices have reached up to 550 euros in the highest case. However, it should also be considered that not all coins reach those prices, and the hammer price can vary depending on demand at the auction.

Based on these factors, an estimated maximum purchase price could be in the range of 250 to 400 euros, considering that the coin has a high condition and there have been examples of high hammer prices in the past. However, given the starting price of 150 euros, it is likely that the hammer price will not exceed 400 euros in this specific auction.

Therefore, a reasonable estimated maximum purchase price could be 350 euros.