For me accumulating a complete set of tools, software, instrumentation and stock to permit building electronics projects has been a long slow process (decades) and it is still going on. This list is my idea of the most effective order in which to acquire new equipment. It takes into account cost and usefulness. I did not exactly follow this path as costs were different when I started - back then a DVM was a very expensive device.
- 3.5 digit DVM (DVMs are the most used instruments and they are now low cost)
- hand tools (needle nose pliers, side cutters, wire strippers, xacto knife, tweezers, screwdrivers, nut drivers, metal shears, vice grips, hack saw, files)
- internet computer (information is the thing that will save you the most time and money)
- temperature controlled soldering station (if you do electronic assembly, you cannot get far without one of these)
- 5 volt power supply (it is important to have reliable bench power supplies - it will make troubleshooting a lot easier)
- stereoscopic microscope (or at least high magnification inspection goggles) electronics are shrinking all the time - it is hard to work effectively if you can't see what you are working on
- vice (a vice is a strong third hand that increases your abilities) (I have at least 4 on my bench)
- variable power supply (this is the second most used electronics instrument - if it displays voltage and current, it will be a lot more useful)
- electric hand drill (electronics need packaging and mechanical interfaces - most projects will need some drilling)
- RLC meter (a DVM does some of this and may be sufficient, but sometimes you need to measure these things - it can save a lot of effort)
- electronic CAD (the fastest way to design something is if you have it stored from the last time - a real time saver)
- oscilloscope (signals are mostly inyteresting when they are changing - and this is the best way to see what they are doing)
- drill press (if you want your projects to look good they need accurate mechanics - a drill press is the minimum to get started on accuracy)
- frequency generator (these simiulate the output of cicuits and sensors and can save a lot of effort)
- electric screwdriver (can save time)
- mechanical CAD (when you want your proects to be aesthetically pleasing and consistent and accurate and repeatable, you need CAD)
- 3D printer (the lowest cost way to build prototypes in many cases)
- hot air rework station (makes SMT work much easier)
By the time you have accumulated this much equipment, you will have enough projects under your belt to know what else you need. For example if you are into radio, there is a different set of equipment that is important than if you are into lighting, or audio, or robotics or IoT or wearables etc.
I have already accumulated more than what is in the above list so I have a fairly complete lab.
Now my wish list is more focused on new modules and parts I would like to embed in electronics projects.
Generally, it is not clear what parts will be needed in future products, but there are some platforms that I expect will be used sooner or later.
I definitely have a couple of Raspberry Pi 3 projects on my to-do list, so they are high on my wish list.
The PSoC Kits are very handy for projects that don't need quite so much horsepower.
And I can always use more 3D printer filament, or if that isn't available a load of Neopixels is bound to find a home sooner or later.
Specific products that are high on my wish list along with why:
PSoC 5 CY8CKIT-059 (the PSoC Creator development environment makes this low-cost Cortex M3 system powerful and easy to use)