Gale already knew the Wangs wouldn't be able to afford the fate lock on short notice. And even if they had the thoughts of purchasing the item, all they could hope to do was to pay in instalments.
Well, Gale wasn't short on money, and he wouldn't care if they pay it at once or in instalments. He literally didn't have a count of how much he had with him. A sixth of his void lock was a good estimate. And that was only the spirit coins. He had various other valuable items.
Anyway, he would lose nothing on this deal. Today or tomorrow, they would pay him back. The best thing about this outcome was that it would make him feel good, helping good people.
Grandma Wang seemed to want this fate-lock for her granddaughter, but the granddaughter wasn't so sure after the price got higher.
Honestly, the price of fate locks was never stable and could go both ways depending on people's needs. There weren't even any associations to control the prices of these items.