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+). This is an important factor, as coins in better condition tend to reach higher prices.

2. Auction History:
- The average hammer price of similar coins in the past is 1415.54 euros.
- The coin has been auctioned 14 times, of which it has sold 13 times, indicating good demand.
- In previous auctions, the hammer price has varied, but there are examples of hammer prices exceeding 2000 euros for coins with similar conditions.

3. Starting and Hammer Prices:
- The current starting price is 1000 euros, which is slightly higher than the average starting price of 892.86 euros.
- In previous auctions, the hammer price has reached up to 3000 euros for coins with a condition of 90, suggesting there is potential for high prices, although the condition of the current coin is slightly lower.

4. Recent Trends: In the most recent auctions, hammer prices have been in the range of 1300 to 1700 euros for similar conditions.

Based on these factors, an estimated maximum purchase price could be in the range of 1500 to 1800 euros, considering that the condition of the coin is slightly lower than those that have reached higher prices in the past. Therefore, a reasonable maximum purchase price could be 1700 euros.