I wave a 1" conduit running about 500' to asome outbuildings, and we are looking at running about 60a service down there from the house. I was hoping to run some fiber alongside (single mode, maybe 6 ...
The place you won't ever regret lots of wire-fishable conduit is any floors that have neither an attic above them or an unfinished basement below. In general, you don't have to worry about every wall ...