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 80 (MS+), indicating that it is in quite good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Historical Prices: By looking at previous auction prices for coins with a similar condition (80-85), we can see that auction prices have varied, but there are examples of auctions reaching up to 180 euros for conditions of 85.

3. Starting Price and Average Hammer Price: The current starting price is 125 euros, and the average hammer price in the past has been 130.2 euros. This suggests that the market is willing to pay a little more than the starting price.

4. Recent Trends: In the most recent auctions, hammer prices have shown a range that can reach up to 240 euros for similar conditions, although this may depend on demand at the time of the auction.

Based on these factors, an estimated maximum purchase price could be in the range of 180 to 200 euros, considering that the condition is good and there are precedents for hammer prices in that range. However, since the starting price is 125 euros, it is likely that buyers will be willing to bid more, especially if there is interest in the coin.

Therefore, an estimated maximum purchase price could be 200 euros.