Accurate household finances

Exploration Stage: Garden of Oblivion
From: Lawrence de Bertrand
Description: I have never dabbled in magic, nor do I even believe in it. When I inherited the mansion, I was busy taking care of the house and had my trusty abacus with me without fail. But where did the abacus go? Finding a reliable abacus.
Completed: So you found an abacus! Oh, how I wish I could go back to the days when calculating income accurately was most important. But I was not born under such fateful stars.