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 the best possible condition.

2. Auction History:
- The average hammer price in previous auctions is 31.25 euros.
- In past auctions, coins with a similar condition (75) have had hammer prices that varied, but some examples are:
- 30 euros (auction on 2020-10-20)
- 40 euros (auction on 2022-02-22)
- 14 euros (auction on 2019-07-03)
- The trend shows that the hammer price can reach up to 40 euros in the case of good demand.

3. Starting Price: The starting price is 25 euros, which is a good starting point.

4. Demand and Supply: Since there are no auctions scheduled in the coming days, this could increase competition among interested bidders.

Based on these factors, an estimated maximum purchase price could be between 35 and 45 euros, considering that the condition is good and there is a history of hammer prices that supports this estimate. A price of 40 euros could be a reasonable target, as it is a midpoint between the average hammer price and the higher prices observed in previous auctions.