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

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 60 euros, and the average starting price in previous auctions is 103.65 euros. This suggests that the current starting price is relatively low compared to the historical average.

3. Previous Hammer Prices: The average hammer price in previous auctions is 164.23 euros. This indicates that, in general, coins of this reference tend to sell for significantly higher prices than their starting price.

4. Historical Data: Looking at previous hammer prices, there are examples of similar coins that have sold for prices that vary considerably, but many of them exceed 100 euros, even reaching up to 325 euros in some cases.

5. Demand and Supply: Since there are no auctions scheduled in the coming days, this could increase the demand for the current coin, potentially leading to a higher hammer price.

Taking all these factors into account, an estimated maximum purchase price could be in the range of 150 to 200 euros, considering that the condition is good and that the historical hammer price suggests that buyers are willing to pay more for coins in similar conditions.

Therefore, a reasonable maximum purchase price could be 180 euros.