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

1. Condition: The coin has a condition rating of 70 (MBC-), indicating that it is in relatively good shape, but not of the highest quality (FDC).

2. Auction History: The coin has been auctioned 7 times and has sold on all occasions. This suggests that there is consistent interest in the coin.

3. Previous Prices:
- The average starting price in previous auctions is 43.17 euros, and the average hammer price is 47.57 euros.
- In past auctions, hammer prices have varied, with a maximum of 130 euros in 2017 and a minimum of 9 euros in 2020.

4. Current Starting Price: The starting price is 25 euros, which is relatively low compared to the average hammer price.

Given that the condition is good and the interest in the coin appears to be solid, an estimated maximum purchase price could be positioned in a range between the average hammer price and the highest price recorded in previous auctions.

Estimated Maximum Purchase Price: Considering all these factors, a reasonable maximum purchase price could be between 70 and 90 euros. This is based on the condition of the coin and the price history, without reaching the highest hammer levels that may not be attainable in this specific auction.