To estimate a maximum purchase price for the coin in question, we can 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 similar coins has been 135.32 euros.
- In previous auctions, hammer prices for coins with a similar condition (75) have varied, but there are examples where they have sold for prices ranging from 110 to 160 euros.

3. Starting Price: The starting price is 40 euros, suggesting that there is considerable room for the hammer price to be higher.

4. Price Trends: In previous auctions, coins with a condition of 75 have reached hammer prices ranging from 49.07 to 240 euros, depending on demand and other factors.

Given that the average hammer price is 135.32 euros and considering the condition of the coin, an estimated maximum purchase price could be in the range of 120 to 160 euros. This is based on the historical hammer prices and the current condition of the coin.

Therefore, a reasonable estimated maximum purchase price for this coin could be 150 euros.