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. Auction History:
- The average hammer price for this coin is 30.06 euros.
- In previous auctions, we have seen hammer prices that varied, but some have reached up to 160 euros in similar or better conditions.
- The last auction with a known hammer price was 35 euros for a coin with a condition of 80.

3. Starting Price and Average Starting Price:
- The current starting price is 25 euros, which is reasonable given the history of starting and hammer prices.
- The average starting price is 20.74 euros, suggesting that the current starting price is competitive.

4. Sales Trends: The coin has been sold in 34 out of 46 auctions, indicating good demand.

Based on these factors, an estimated maximum purchase price could be in the range of 35 to 50 euros. This is based on the history of hammer prices and the current condition of the coin. Therefore, a reasonable maximum purchase price could be 45 euros.