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

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

2. Historical Prices: Looking at previous auction prices for coins with similar conditions:
- In past auctions, coins with a condition of 70 have reached hammer prices of up to 95 euros.
- Coins with a condition of 85 have reached hammer prices of up to 220 euros.
- The last auction with a condition of 90 had a hammer price of 190 euros.

3. Average Hammer Price: The average hammer price for this coin is 130.45 euros, which is also a good indicator.

4. Starting Price and Average Starting Price: The current starting price is 15 euros, and the average starting price is 70.42 euros. This suggests that the starting price is quite low compared to previous hammer prices.

5. Recent Trends: In the most recent auction, a coin with a condition of 85 was hammered at 180 euros, indicating a growing interest in coins of good condition.

Taking all these factors into account, an estimated maximum purchase price for the coin with a condition of 75 could be in the range of 100 to 150 euros. This is based on the analysis of previous hammer prices and the current condition of the coin. A price of 120 euros could be a reasonable target, as it falls in the middle of this range and is consistent with previous hammer prices.