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

1. Current Condition: The coin has a condition of 70 (MBC-). This is an important factor, as coins in better condition tend to reach higher prices.

2. Previous Prices: By observing previous auction prices for coins with similar conditions, we can see that:
- In 2018, a coin with a condition of 70 was auctioned for 110 euros.
- In 2021, a coin with a condition of 95 was auctioned for 150 euros.
- In 2024, a coin with a condition of 70 was auctioned for 45 euros.

3. Average Auction Price: The average auction price for this coin is 100.83 euros, which gives us a good reference.

4. Starting Price and Average Starting Price: The current starting price is 50 euros, and the average starting price is 76.58 euros. This suggests that interest in the coin may be moderate.

5. Auction Trends: The coin has been auctioned 13 times, of which 12 have sold. This indicates a consistent interest in the coin.

Based on these factors, an estimated maximum purchase price could be in the range of 100 to 125 euros, considering that condition is a key factor and that the highest auction price for a similar condition was 110 euros.

Therefore, a reasonable estimated maximum purchase price could be 120 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 70 (VF-), indicating that it is in an acceptable state, but not of the highest quality.

2. Auction History:
- The average hammer price for coins of similar condition (70) in the past has been approximately 50 to 90 euros, with some auctions reaching up to 110 euros.
- In previous auctions, hammer prices for coins with a condition of 70 have varied, but the range seems to be between 40 and 90 euros.

3. Starting Price and Average Hammer Price:
- The current starting price is 20 euros, which is relatively low compared to the average hammer price of 86.06 euros.
- The average starting price of 50.63 euros also suggests that there is potential for an increase in the hammer price.

4. Recent Trends:
- In the most recent auctions, hammer prices have shown a trend of being in the range of 75 to 110 euros for coins of similar condition.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 80 to 110 euros. This is based on the historical hammer prices for coins of similar condition and the potential for an increase in the hammer price in the current auction.

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

1. Current Condition: The coin is in a condition of 90 (EF), which indicates that it is in good shape. This generally translates to a higher price compared to coins in lower conditions.

2. Auction History:
- The average hammer price for similar coins has been 47 euros.
- In previous auctions, coins with a similar condition (90) have reached hammer prices of up to 50 euros.

3. Starting Price: The starting price is 20 euros, which is relatively low compared to previous hammer prices.

4. Price Trends: Observing previous hammer prices, it seems there is a trend for coins in good condition (EF) to sell for above 40 euros.

Based on these factors, an estimated maximum purchase price for this coin could be between 50 and 60 euros, considering that the condition is favorable and that the price history supports this estimate. Therefore, a reasonable maximum purchase price could be 55 euros.