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

1. Current Condition: The coin has a condition of 25 (BC), which indicates that it is in quite low condition. This will negatively affect its value compared to coins in better condition.

2. Historical Prices: By looking at previous auction prices, we can see that coins of this reference have had a fairly wide price range, depending on their condition. For example:
- In 2020, a coin with a condition of 70 was auctioned for 95 euros.
- In 2020, another with a condition of 80 was auctioned for 220 euros.
- In 2022, a coin with a condition of 30 was auctioned for 190 euros.

3. Average Auction Price: The average auction price for this coin is 202.64 euros, but this includes coins in better conditions.

4. Current Starting Price and Average Starting Price: The current starting price is 70 euros, and the average starting price in the past has been 130.45 euros.

Given that the condition of the coin is quite low (25), it is reasonable to assume that its auction price will not reach the levels of coins in better condition. However, considering that there have been successful sales in the past and interest in the coin, an estimated maximum purchase price could be set at a lower range.

Estimated Maximum Purchase Price: Based on the previous information, a reasonable maximum purchase price could be between 80 and 100 euros, taking into account the condition and previous auction prices. This would allow for a competitive offer without exceeding the value it could reach at auction.