I need your help. What size do i build the buildings in my world? At real size, but in unreal units? Or at the defaults of a few centimeters as actors are when placed. At real size my lights are vanishing from all views. I am having a very hard time starting. After a week of tutorials and youtube videos, i feel like i should be past the banging my head stage. Thank you for your help.
They should be to scale. You can always put the mannequin in the scene if you’re not sure.
What pack do you have with buildings that are only a few cm high? Sounds wrong… 
You should think of them as “real size in Unreal units” – a player might be 180-190 units tall, for example.
Now, most actual indoor spaces are too small for good gameplay – they will look really cramped on the screen. An interior door may be 32 inches wide (80 unreal units) but that’s not wide enough for gameplay (and may not even be wide enough for the default character.)
Thus, you’ll actually want to build “standard” doors to be two meters wide and three meters tall, and “roomy” doors to be three meters wide and four meters tall. Similarly, inner ceilings will generally want to be 4 meters at least, again, to look and play good from a gameplay point of view.
If you’re not doing a game, but an arch viz project, then stick to exact measurements, though 
1 Like