A gunman remains at large after shooting a 20-year-old outside his Sydney home as the victim's mother and sister listened to it unfold inside.

Blood splatters still stained the steps outside the Heckenberg home of Aseel Abbas on Saturday, almost 24 hours after he was shot in the hip.

Neighbours said they heard shouting before a gunshot rang out on North Liverpool Road just after 5pm on Friday.

One nearby resident said she saw Mr Abbas, the youngest of four siblings, talking to someone in a black car 15 minutes before he was shot.