To estimate a maximum purchase price for the coin in question, we can consider several factors based on the provided data:

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

2. Starting Price and Average Hammer Price: The starting price is 80 euros, and the average hammer price in previous auctions is 131.21 euros. This suggests that, on average, similar coins sell for a significantly higher price than their starting price.

3. Sales History: The coin has been auctioned 214 times, of which 192 have been sold. This indicates good demand and a history of successful sales.

4. Previous Prices: Looking at previous hammer prices for coins with a similar condition (80-85), we can see that they have reached hammer prices that vary, but some have gone for 200 euros or more in similar conditions.

5. Recent Trends: In the most recent auctions, hammer prices have shown an increase, which could indicate an upward trend in the value of this coin.

Based on these factors, an estimated maximum purchase price could be in the range of 150 to 200 euros. This is based on the average hammer price and the price history of coins with a similar condition.

Therefore, a reasonable maximum purchase price could be 200 euros.