To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially the previous auction prices and the current condition of the coin.

1. Current Condition: The coin has a condition of 75 (MBC), indicating that it is in fairly good shape, but not of the highest quality (FDC).

2. Previous Auction Prices: By looking at the auction prices of coins with similar conditions (around 75-80), we can see that the auction prices have varied. For example:
- In previous auctions, coins with a condition of 75 have reached auction prices of up to 130 euros.
- Coins with a condition of 80 have reached auction prices of up to 200 euros.

3. Average Auction Price: The average auction price for this coin is 96.38 euros, which is also a good indicator.

4. Price Trends: Since the coin has been auctioned 151 times and has had a high sales percentage (139 out of 151), this suggests that there is a consistent interest in this coin.

5. Starting Price: The starting price is 60 euros, which is reasonable and could attract bidders.

Based on these factors, an estimated maximum purchase price for this coin could be between 120 and 150 euros, considering that the condition is good and there is a history of auction prices that supports this estimate.

Therefore, a reasonable maximum purchase price could be 150 euros.