In our company (747) there are 2 different scenarios: Precision approach (ILS) and non-precision approach. For precision approaches, gear come down after glideslope is alive, then landing flaps at G/S intercept. Landing checklist comes immediately after landing flaps are selected.
For non-precision approaches, airplane is configured and landing checklist completed prior to IAF, so any required timing can be done with a stable airspeed.