>>2874892>twilight shotyou nailed the best time of day for exterior architectural shots when the inside lights are glowing warmly and the sky is turning a deep blue.
Best method for perfect exterior is to set up your camera on a tripod just before golden hour, then take shots every few minutes over the next hour as the sun sets and the sky turns darker blue.
You want to get a great exposure for the building, another exposure for just the lights in the windows (so they're not blown out), and a third exposure for the sky. This takes patience because the light conditions are constantly changing as the sun goes down, so you'll need to just keep chimping.
Combine the sky, exterior, and light exposures in photoshop. Youtube has some great tutorials, just search twilight+shot+real+estate.