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 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 a similar condition (75), we can see that they have varied. For example, in previous auctions, coins with a condition of 75 have reached hammer prices of 23, 20, and 45 euros.

3. Average Hammer Price: The average hammer price for this particular coin is 101.08 euros, but this may be influenced by coins in better condition.

4. Average Starting Price: The average starting price is 69.06 euros, which can give an idea of what sellers expect to obtain.

5. Recent Trends: In the most recent auctions, hammer prices have shown a trend of being higher, especially for coins in good condition.

Given all this, an estimated maximum purchase price for this coin, considering its condition and previous hammer prices, could be in the range of 45 to 75 euros. This is based on the fact that, although the coin is in decent condition, it is not of the highest quality, and previous hammer prices for similar coins have been lower.

Therefore, a reasonable maximum purchase price could be 70 euros.