in the case of a construction anyhow, this is the best way

voilà , ça feras un franc

Bance you gave the right answer
now allow me to correct a big source of problems: avoid like the devil making sketches referenced to faces, do them on the general plans and use the "Inverted" flag if necessary
Avent that others tell you that they do this in 2 sketches

I think of the Step format you will have the saving of the finished object, importable into CAD which reads the STEP format
you will no longer see the tree structure or the sketches used, but you will be able to continue working on it via your other CAD

This is an important feature to know
full name is DatumPlan
it is the equivalent of one of the 3 main planes but adjustable in all positions
have a look in the Wiki: Google > Fc/tuto/Datumplan

seeing the underlying image, I suspected this reason
Furthermore you can use the main axes and when everything is finished, move the body using its placement
the disadvantage is that in the event of a copy or clone, it will return to its origin
you can also use one of the assembly workshops

in this case: on a Datum you draw the rectangle above, on the XY plane the median plane and Loft between the 2
Same for the bottom

I vote yes like 49%, 49% vote no, 1% don't care and 1% responds "get rid of glassy politicians"

I suppose the sides have the same angles as the face
I measure them and report them in a side sketch to make Pocket, and mirror for the other side

the 2 mirrors are not taken into account even though they are in the container, I don't know why
you do a fusion of each of them and it works