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 30 (BC+), indicating that it is not in the best condition. This generally reduces its value compared to coins in better condition.

2. Auction History:
- The average hammer price for similar coins in the past is 146.6 euros.
- The coin has been auctioned 15 times, of which it has sold 11 times, indicating good demand.
- Previous hammer prices for this coin varied, but there are examples of auctions reaching up to 650 euros in superior conditions.

3. Starting Price and Average Starting Price:
- The current starting price is 12 euros, which is quite low compared to the average starting price of 62.92 euros.

4. Recent Trends: In the most recent auction, the coin was offered at a starting price of 12 euros and was estimated at 20 euros, although it did not sell. This may indicate that interest in this coin has decreased or that the starting price is not attractive.

5. Condition of Similar Coins: Coins with higher conditions (such as 70, 75, 80, 85) have reached significantly higher hammer prices. This suggests that condition is a critical factor in determining price.

### Estimated Maximum Purchase Price
Given that the condition of the coin is 30 (BC+), and considering the auction price history and the average starting price, a reasonable maximum purchase price could be:

- Estimated Maximum Price: 30-40 euros.

This range takes into account the current condition and historical interest in the coin, as well as the fact that the starting price is low. If the auction generates interest, the price could approach the upper end of this range.

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

1. Current Condition: The coin has a condition of 30 (BC+), which indicates that it is not in very good shape. This will negatively affect its value compared to coins in better condition.

2. Auction History: By looking at previous auction prices, we can see that coins in better condition (for example, 85 and 95) have reached hammer prices of up to 220 euros. However, coins with lower condition have had lower hammer prices.

3. Average Hammer Price: The average hammer price for this coin is 102.91 euros, which gives us an idea of the general market value.

4. Starting Price: The current starting price is 12 euros, suggesting that the seller has low expectations compared to the average hammer price.

5. Sales Trends: The coin has been auctioned 12 times, of which 11 have been sold, indicating good demand in the market.

Given that the condition of the coin is relatively low (30), and considering the auction price history, an estimated maximum purchase price could be set in a lower range than the average hammer price.

Taking all these factors into account, an estimated maximum purchase price could be around 40-50 euros. This reflects a balance between the current condition and the price history, as well as the demand observed in previous auctions.

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 25 (BC), which indicates that it is not in very good shape. This generally reduces its value compared to coins in better condition.

2. Auction History: By observing the hammer prices of similar coins in the past, we can see that prices vary significantly depending on the condition. For example, coins with higher grades (such as 80 or 90) have reached hammer prices of up to 190 euros.

3. Starting Price and Previous Prices: The current starting price is 15 euros, and the average hammer price in the past for similar coins is approximately 98.9 euros. However, given that the condition of this coin is low, it is likely that the hammer price will be below the average.

4. Recent Trends: In recent auctions, hammer prices for coins in similar conditions have ranged between 30 and 50 euros, depending on demand and rarity.

Taking all these factors into account, an estimated maximum purchase price for this coin, considering its condition and auction history, could be between 25 and 40 euros. This reflects a balance between the state of the coin and previous hammer prices for coins of similar condition.

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

1. Current Condition: The coin has a condition rating of 25 (BC), indicating that it is not in very good shape. This will negatively affect its value compared to coins in better condition.

2. Auction History:
- The average starting price for similar coins is 135.53 euros, and the average hammer price is 306.31 euros.
- In the past, coins with a condition rating of 70 have reached hammer prices of up to 950 euros. However, these coins are in much better condition than the one we are evaluating.

3. Sales Trends:
- Out of the 58 times this coin has been auctioned, it has sold on 46 occasions, indicating good demand.
- The current starting price is 20 euros, which is relatively low compared to the average starting price of other auctions.

4. Previous Prices:
- The hammer prices for coins with similar conditions (BC) have been significantly lower. For example, in previous auctions, hammer prices for coins in similar conditions have ranged from 20 to 70 euros.

Given all this, and considering that the coin's condition is a critical factor limiting its value, an estimated maximum purchase price could be in the range of 30 to 50 euros. This is based on the fact that, although there is a history of higher prices for coins in better condition, the current condition of this coin limits its appeal to collectors.

Therefore, a reasonable maximum purchase price could be 40 euros.

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

1. Current Condition: The coin has a condition of 80 (MS+), which indicates 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 in previous auctions is 69.02 euros.
- The last auction for this coin had a hammer price of 65 euros with a condition of 80.
- In previous auctions, hammer prices have varied, but there are examples of hammer prices exceeding 200 euros for coins of similar or better condition.

3. Starting Price and Average Starting Price:
- The current starting price is 20 euros, which is relatively low compared to the average starting price of 35.64 euros.

4. Sales Trends: The coin has been auctioned 15 times, of which 9 have been sold. This indicates a consistent interest in the coin, which may influence its price.

Based on these factors, an estimated maximum purchase price could be in the range of 80 to 100 euros, considering that the condition is good and that the auction price history suggests it could reach higher figures in auctions. However, since the starting price is low, it could be a good opportunity to acquire it at a reasonable price.

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

1. Current Condition: The coin has a condition rating of 30 (BC+), which indicates that it is not in the best condition. This generally reduces its value compared to coins in better condition.

2. Historical Prices: By looking at the auction prices of coins with a similar condition (30) in the past, we can see that the auction prices have varied. For example, in previous auctions, coins with a condition of 30 have reached hammer prices ranging from 10 to 20 euros.

3. Average Hammer Price: The average hammer price for this particular coin is 98.02 euros, but this includes coins in better condition. Therefore, it is not a good indicator for our specific coin.

4. Starting Price: The starting price is 15 euros, which can be a good starting point for the auction.

5. Recent Trends: In the most recent auctions, hammer prices for coins with similar conditions have been in the range of 20 to 35 euros.

Taking all these factors into account, an estimated maximum purchase price for this coin, considering its condition and historical prices, could be between 20 and 30 euros. This reflects a balance between the condition of the coin and previous hammer prices.