https://www.youtube.com/watch?v=QAAYHTuqm9M
was just perfect for me.

Yes, it is one of the better YouTube videos. However, it shows a (rough, inaccurate) free-hand illustration that does not show working with accurate measurements: does not use Wall/Room-tool+ENTER, Dimensions-double-click, Wall/Room-double-click, multiple-select-modify, Ctrl-move, Shift-move, etc, etc. So therefore that video can also be a bit misleading and does not really show the SH3D features you seem to need: "allow me to be very precise and accurate". Just know that SH3D has many features that makes it easier to work with mm precision not shown in the video.

I have done two old buildings in SH3D. And yes, of course, it takes some more time when all walls are different and most angles are off by a couple of degrees. But my drawings are accurate with an error margin of a couple of mm. So I disagree with Adjusting them would take ages in SW.

Long and short of it is, that equipped with a Laser Measure (forget ultra-sound with laser pointers), a laser level and a piece of paper, it was fairly easy just to enter accurate measures in SH3D afterwards.

Do not get me wrong, I also use other software, but in terms of drawing up and editing an accurate house plan, I have yet to come anywhere near the speed and ease of use of SH3D with any other software. Once you learn the tricks, that is.

ok