To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially the previous auction prices and the coin's condition.

1. Condition: The coin to be auctioned has a condition of 80 (MBC+). This is an important factor, as coins in better condition tend to reach higher prices.

2. Previous auction prices:
- In previous auctions, coins with a condition of 80 have had hammer prices that varied, but some examples are:
- 2018-10-17: €310
- 2018-10-17: €160
- 2015-12-16: €200
- 2022-04-27: €165
- 2022-02-17: €380
- The highest hammer price for a coin with a similar condition was €380.

3. Average hammer price: The average hammer price for this coin is €187.48, indicating that, in general, coins of this reference tend to sell for below their estimated price.

4. Starting price: The starting price is €125, suggesting that the seller expects a reasonable price for the coin.

5. Recent trends: In the most recent auctions, hammer prices have shown a trend of being higher, especially for coins with a condition of 80 or above.

Based on these factors, an estimated maximum purchase price could be in the range of €250 to €300, considering that the condition is good and there are precedents of higher hammer prices in the past. This also takes into account the starting price and the interest that the coin might generate in the auction.