I am trying to use the Plan view module to draw room elevations.For example a drawing showing the position of a monitor to be mounted on a wall. So it needs to be drawn to scale and exact dimensions shown.

If I add a monitor product to the plan view, its not to scale and I also cannot amend the dimensions in the Property window. The same applies if I just use a square to represent a monitor. I know you can drag the symbol/product to resize, but to get them exact is laborious and takes far too much time.

Is there a reason the products are not to scale, and why the dimensions in the property window cannot be edited. I know you can unlock the object, but it only applies to individual elements of the object not the whole object and again is laborious and time consuming.
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Thanks
Kevin‌‌‌‌‌