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

1. Condition: The coin has a condition of 75 (MBC), which indicates that it is in an acceptable state, but not of the highest quality. This can influence the price, as coins in better condition tend to reach higher prices.

2. Auction history:
- In the past, coins of the same reference with similar conditions (75 and 80) have been auctioned.
- Previous hammer prices have been 135 (in 2015) and 75 (in 2021) for conditions of 75 and 80, respectively.
- The 2022 auction shows a starting price of 60 and an estimated price of 100 for a coin with a condition of 100, indicating that the price can vary significantly depending on the condition.

3. Starting price and average prices:
- The current starting price is 110 euros, and the average hammer price in the past has been 105 euros. This suggests that the market is willing to pay close to this price, but there may be fluctuations depending on demand.

4. Auction trends: Given that there have been more auctions and successful sales in the past, this may indicate sustained interest in this coin, which could drive up its price.

Based on these factors, an estimated maximum purchase price could be in the range of 100 to 120 euros, considering that the condition is a limiting factor and that the starting price is 110 euros. Therefore, a reasonable maximum purchase price could be 120 euros.