My new cordless phone came with a horrible wall mount kit that only worked form the main base station and not for the satellite units. After a few measurements and a couple of test prints, I had a aesthetic wall mount kit that performs great. The satellite charger slips in the top and is held in by gravity. The power cord feeds in through a hole in the bottom of the mount.
I drew the design in FreeCAD. I used the draft and fillet features to get a nice smooth shape that snuggly fits the provided base unit. Such operations would have been very difficult in openscad.
1) Print (I used abs at 0.20 mm 30% infill at 240C)
2) Mark and drill wall. Either into studs or use wall anchors
3) Screw up mount
4) Insert satellite charging station.
5) Connect power cord
6) Install phone.