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

2. Current Starting Price and Previous Prices: The current starting price is 150 euros. In previous auctions, we have seen hammer prices that vary, but some have reached up to 320 euros under similar conditions.

3. Sales History: Out of the 24 times it has been auctioned, it has sold 22 times, indicating good demand. The average hammer price in the past has been 179.43 euros, suggesting that buyers are willing to pay more than the starting price on many occasions.

4. Recent Trends: In the most recent auctions, hammer prices have been relatively high, with a hammer price of 320 euros in a recent auction for a coin with similar condition.

5. Data-Based Estimation: Given that the average hammer price is 179.43 euros and considering that the condition of this coin is good (80), an estimated maximum purchase price could be set in a range above the average hammer price, but not as high as the highest recorded price.

Taking all these factors into account, an estimated maximum purchase price for this coin could be approximately 250 euros. This reflects a balance between the condition, historical demand, and previous hammer prices.