As long as Xue Dagui was friendly with the other families, ice would be sold.
Now, Xue Dagui had to come back with Xue Sifu to pick some grapes and bring them to the town or county to convince the rich families to buy them.
The grapes were sweeter than other people's grapes, and there weren't many grapes sold around. No matter what, those wealthy families would want to buy them when they saw them.
Especially the red grapes. Even if they were sold at a much higher price than other grapes, those rich families were willing to buy them. Moreover, they would buy a lot of them. They did not lack the money. It would be considered a small amount of money.