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 70 (MS-). This is an important factor, as coins in better condition tend to reach higher prices.

2. Auction History:
- The average hammer price for similar coins in condition 70 has been approximately 170-260 euros in previous auctions.
- In recent auctions, coins with similar condition (70) have sold for prices ranging from 130 to 290 euros.

3. Starting Price and Average Hammer Price:
- The current starting price is 150 euros, which is reasonable compared to the average hammer price of 258.45 euros.
- The average starting price of 162.34 euros also suggests that the starting price is competitive.

4. Recent Trends: In the most recent auctions, coins with a condition of 70 have had hammer prices around 290 euros, indicating a growing interest in this type of coin.

5. Proximity of Upcoming Auctions: There are two auctions scheduled in the coming days, which could influence demand and price.

Based on these factors, an estimated maximum purchase price for this coin could be between 250 and 300 euros, considering that interest in coins of similar condition has increased and that the hammer price in recent auctions has been favorable.