The core activity of Rudolf Fasler Aarau AG encompasses three main areas:
1. **Trust Services**: The company provides trust services, including financial accounting, payroll accounting, preparation of annual accounts, payroll administration, VAT declarations, and tax returns.
2. **Estate Liquidations and Consulting**: The company supports the liquidation of estates, including the settlement of estate debts, the distribution of legacies, and the division of the estate according to the instructions of the deceased or as prescribed by law.
3. **Executor Services**: The company offers executor services, including the settlement of estate debts, the distribution of legacies, and the division of the estate according to the instructions of the deceased or as prescribed by law.
Overall, the core activity of the company can be described as comprehensive services in the field of estate administration and liquidation, including trust and consulting services.