Guild infamy should be able to go into the negative, until -100. When you reach -100 you stop losing.
what would it do? if a guilds infamy went below 0, they would be temporarily unable to upgrade their guild and would be granted the “Pathetic Guild” rank.
If a guilds infamy went to -100, they would be granted the “Worthless Guild” rank. Guilds with the “Worthless Guild” rank would be unable to deposit or withdraw money from their bank.
reason to add: it would be funny to see a pathetic guild or a worthless guild and people can shit on them.