Responded to call for power loss in guest bedrooms. Upon arrival customer advised power is intermittent in both rooms and breaker is not tripping at the time of the power loss but power restores without any repair. Inspected guest bedrooms. Tested all outlets in both rooms. With outlet tester found multiple outlets have failing wiring connections. Advised customer. Inspected panel. Found double tapped neutrals and 25+ year old breakers that are weak and worn. Also found a small amount of corrosion on the bus bars in the panel. Advised customer of the concerns with corrosion, double tapped neutrals, and weak connections at switches and outlets. While inspecting panel customer observed arching at the bedroom breaker. Advised customer with multiple issues with the bedroom electrical circuit replacing the breaker is needed to prevent further damage but is not guaranteed to completely eliminate the power loss issues. Customer agreed to replacing the breaker. Removed existing tandem breake