To estimate a maximum purchase price for the coin in question, we can analyze several factors:

1. Current Condition: The coin has a condition rating of 80 (MBC+), which indicates 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 similar coins in the past is 266.15 euros.
- The last auction of a coin with a similar condition (80) had a hammer price of 550 euros in March 2023.
- In other auctions, coins with a condition of 80 have reached hammer prices of 370 euros and 340 euros.

3. Starting Price: The starting price is 200 euros, which is a good starting point, but the hammer price is usually significantly higher.

4. Price Trends: Observing previous hammer prices, it seems there is a trend for coins with a condition of 80 to sell in a range of 300 to 550 euros, depending on demand and other market factors.

Based on this data, an estimated maximum purchase price for this coin could be in the range of 350 to 400 euros. This is based on the auction price history for coins of similar condition and the interest it might generate in the auction.