Nothing more satisfying than making something that cheaper, and also exceed the quality of buying ready-to-use product.
CAD, EDA, IDE, and correct toolkits to the rescue!
EDIT:
In case someone want to delve in hobbyist/maker/diy world, here are some useful stuffs that available free:
3D CAD:
Freecad - FOSS 3D CAD software that available cross-platform.
Autodesk Fusion - Not so great alternative but servicable, Free plan have certain limitation.
EDA:
KiCAD - Designing electronic project has never been so easy. This one far superior than Autodesk Eagle crap.
EasyEDA - Free online and desktop EDA software that can be used for alternative.
(Microcontroller) IDE:
VSCode/Codium + PlatformIO - Most affordable, off-the-shelf controller are programmable with PlatformIO and enough for most average joe projects. Arduino IDE may be superior for newcomer but I recommend this as you have more leeway in which framework and board you can get out of single extension for Text Editor.
Toolkits:
Digital Multimeter - Most common electronics can be troubleshoot’d with digital multimeter to identify the problem.
Cheap E-Bay caliper (or any cheap caliper) - For most DIY project, cheap digital caliper are enough to measure dimension unless you really need 3 digit precision.
To be honest I don’t have 3d printer myself and rarely print to make a case, the electric bill really putting me off to own one. Most of time I used those pre-made abs plastic project box that you can cut/drill holes and come with various size. Other than that, sometime it feels “costly” to make something if you didn’t plan ahead or not really going to use the project.