Quick answer: confirm both sides of the round trip
For a Singapore-origin Muar family visit or errand, prepare the Singapore pickup and Muar drop-off first, then confirm the return date, ready time and exact Muar pickup point before the return. Keep the plan in one WhatsApp thread so an address, delay or passenger update does not become a separate booking instruction. This article supports a Singapore-origin round trip; a standalone Malaysia-origin Muar-to-Singapore trip belongs to the Malaysia-to-Singapore route owner.
