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

1. Coin Condition: The coin has a condition rating of 80 (MS+), 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 245.58 euros, suggesting that, in general, coins of this reference sell for relatively high prices.
- In past auctions, we have seen hammer prices that varied significantly, but many of them are above 100 euros, especially for coins in similar conditions.

3. Starting Price and Previous Prices:
- The current starting price is 45 euros, which is quite low compared to the average hammer price. This suggests that there could be a good buying opportunity.
- In previous auctions, coins with a similar condition have reached hammer prices of up to 480 euros.

4. Recent Trends: Recent auctions show that coins with similar conditions have had hammer prices ranging from 100-200 euros, and some have reached higher prices depending on demand.

Based on these factors, an estimated maximum purchase price for this coin could be between 200 and 300 euros, considering that the condition is good and that the hammer price history supports this estimate. However, since the starting price is 45 euros, it may be possible to acquire it for a price below this range, depending on the competition in the auction.