Can somebody explain the best way (which will give best performance) to set up a wifi network across a large house?

If money were almost no object, how would one set it up so that you could get a strong wifi signal in every room from the basement to the attic? (preferably while staying on the same wifi network eg. so that it doesn't require any skill on the part of the user to change networks etc.) The goal being to be able to watch streaming video in any room on an iPad/iPhone etc.

I am eager to learn how this is done!
I didn't find the right solution from the internet.

References: https://www.cnet.com/discussions/how...-house-602528/
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