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), which indicates that it is in fairly good shape, but not of the highest quality (FDC).

2. Auction History:
- The average hammer price for coins of similar condition (75) in the past has been approximately 25-35 euros, with some auctions reaching up to 130 euros for higher conditions.
- In previous auctions, the hammer prices for coins with a condition of 75 have varied, but the range seems to be between 20 and 35 euros, with some exceptional cases.

3. Price Trends:
- The average starting price has been 43.46 euros, but this may not reflect the actual hammer price, which is more relevant for estimation.
- The coin has been auctioned 62 times, with a sales percentage of 87%, indicating good demand.

4. Comparison with Previous Prices:
- In recent auctions, the hammer price for coins in condition 75 has been in the range of 20 to 35 euros, with a higher hammer price of 45 euros on some occasions.

Based on these factors, an estimated maximum purchase price for the coin in condition 75 could be in the range of 35 to 50 euros. This takes into account the possibility that interest in the coin may be higher in the current auction, but also considers that the condition is not the highest.

Therefore, a reasonable maximum purchase price could be 45 euros.