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 rating of 70 (VF-). 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 has been 353.51 euros.
- In previous auctions, coins with a similar condition (70) have had hammer prices that vary, but there are examples where they sold for 130 euros (2020-07-02) and 166 euros (2018-04-24).

3. Starting Price and Average Starting Price:
- The current starting price is 110 euros, which is relatively low compared to the average hammer price.
- The average starting price of 212.97 euros also suggests that there is potential for an increase in the hammer price.

4. Sales Trends: The coin has been sold in 75 out of 81 auctions, indicating good demand.

5. Recent Hammer Prices: In the most recent auctions, hammer prices have ranged from 220 to 551 euros for similar conditions.

Based on these factors, an estimated maximum purchase price could be in the range of 250 to 350 euros, considering that the condition is a limiting factor and that the starting price is relatively low.

Therefore, a reasonable maximum purchase price could be 350 euros.