To estimate a maximum purchase price for the coin that will be auctioned, we will consider several factors, including the starting price, the auction price history of similar coins, and the lack of information regarding the condition of the coin in question.

1. Starting Price: 180 euros.
2. Auction Price History:
- In previous auctions, hammer prices have varied significantly, with some examples of auctions in the range of 60 to 650 euros, depending on the condition and other factors.
- Most hammer prices for coins of similar condition (when information is available) seem to be in the range of 30 to 300 euros, with some exceptional cases reaching higher prices.

3. Average Hammer Price: 98.9 euros, indicating that, in general, coins of this reference tend to sell for less than their starting price.

4. Condition: The lack of information about the condition of this coin makes it difficult to predict its exact value. However, if we consider that most coins of medium to high condition tend to sell for a higher price, we could assume that this coin might be in a similar range.

5. Auction Trends: Since it will be auctioned in the coming days and there is considerable interest (2 scheduled auctions), this could increase competition and, therefore, the hammer price.

### Maximum Purchase Price Estimate:
Based on the starting price and the auction price history, a reasonable maximum purchase price could be 20-30% above the starting price, considering the possibility that the coin has an attractive value for collectors.

Maximum Purchase Estimate:
- Starting Price: 180 euros
- 20-30% Increase: 36 to 54 euros

Therefore, the estimated maximum purchase price could be in the range of 216 to 234 euros.

However, since the auction market can be unpredictable, it is advisable to be prepared to adjust this figure according to the competition in the auction and the market response.