Best amount of coins to sell

To those of you who sell gold for coins: what's the amount of coins that you have found to sell better?

Generally, I'd expect lower amounts where the coin cost is 9-14 coins, to be easiest to sell.

I've usually sold with prices ranging from 10 to 30+ coins without much of an issue. Just gotta look at what others are offering at the time.

Thanks for your input.