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 has a condition rating of 95 (EBC+), indicating that it is in very good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Starting Price and Previous Prices: The current starting price is 70 euros, and the average hammer price in previous auctions is 85.68 euros. This suggests that, in general, coins of this reference tend to sell for above the starting price.

3. Auction History: In the auction history, we have seen hammer prices that varied, but there are several examples where the coin has sold for above 80 euros, even reaching up to 135 euros in a previous auction.

4. Price Trends: Since the coin has been auctioned 28 times and has sold 26 of those times, there is a high sell-through rate, indicating that there is demand for this coin.

Based on these factors, an estimated maximum purchase price could be in the range of 100 to 120 euros, considering that the condition is high and that the price history shows similar coins have reached hammer prices in that range.

Therefore, a reasonable maximum purchase price could be 110 euros.