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

1. Condition: The coin has a condition of 70 (MBC-), which indicates that it is in an acceptable state, but not of the highest quality. This influences the price, as coins in better condition tend to reach higher prices.

2. Previous starting and hammer prices:
- The average starting price is 63.23 euros and the average hammer price is 97.45 euros.
- In previous auctions, the hammer price has varied considerably, with some auctions reaching up to 260 euros (in the case of a coin with a condition of 85).

3. Sales trends: The coin has been sold in 49 out of 56 auctions, indicating good demand. Additionally, the fact that it will be auctioned again soon suggests that interest in the coin remains.

4. Comparison with previous prices:
- In recent auctions, hammer prices for coins with similar conditions (70) have been around 70-120 euros.
- The last auction of a coin with a condition of 70 had a hammer price of 90 euros.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 90 to 120 euros. This is based on current interest, the condition of the coin, and previous hammer prices. However, since the auction market can be volatile, it is advisable to keep an eye on the auction and adjust the bid according to the competition.