Watching Blender Bros, and the guys constantly name drop these 4. I figured out the red box boolean thing was box cutter, but the other 3 goes over my head and i get confused.
And reading the addon descriptions doesnt help me identify which is which and whats being used for what.
i need help
Well… (very) general speaking (and so somekind of false): different approaches helpfull for hard surface modelling… If you don’t get the different ideas from the description… then you are not deep enough into HSM…
Like me 
… i still didn’t found out which i should try… i even have the carver tool and the bool tool not enabled… just using simple extrude and bevel 
They are all separate addons, but you can buy a HardOps/Boxcutter bundle called HopsCutter, (it’s the same, just cheaper than buying both separately).
Machine Tools is a free addon for workflow and Mesh Machine is a paid addon for dealing with, well, mesh issues.
I’ve had all of them for a while and yes, for non-organic modelling, they are, to me, almost indispensable.
HardOps is great for general working, I don’t think I ever load Blender without bringing it into play at some point. So things like making curves from edges, extracting plates or adding bevels to points etc, etc. There really is so much to it.
As you say, Boxcutter is a boolean / build addon, but don’t think it’s restricted to just cutting, you can use it in “make” mode to block out shapes and Blender Bros show this in a few videos.
Machine Tools provides pie menus and hotkey functionality which speeds up certain workflow things, so it becomes a one-click rather than going through menus and doing 2 or 3 things.
Mesh machine is worth it alone for how it handles bevels, allowing you to re-define them at any point, remove them and crucially, with “unf*ck”, tidy up crossing bevels, also darned useful for sorting problems after an inset may squash a rounded corner too much.
As you may have gathered, I am a fan of all of them, though machine tools is the one I use the least because I have my own preferences on keymaps. The others though are, as I say, part of my workflow whenever I use Blender.
I’ll grant you, they are not cheap, but they are powerful and if you do hard-surface / non-organic work they will make your life a lot easier. Ponte from Blender Bros has videos on mesh machine & machine tools and there are a lot of videos on Youtube about HopsCutter, there is a ton of functionality in them and I barely scratch the surface of it normally.
Is mesh machine tools really just 1 dollar?
Seems too cheap for something that powerful.
Am i looking at the right addon?
Do you mean MACHIN3tools?
And yes it is actually a free toolset but BM has a minimum price of 1$ for anything sold…
The DeusEx version I believe is 10$± , and worth it in my book, as It includes the Edge Constrained Transform tool, as well as Group Gizmos and the Punch It tool.
As RSEhlers says, mesh machine no, that’s $40, but go to gumroad and Machine Tools is free:
I’m over simplifying this quite a bit
Box Cutter: basically an advanced set of Boolean tools and functions
https://hardops-manual.readthedocs.io/en/latest/getstarted/
Hard Ops: a set of tools for advanced hard surface modeling. Namely concertation on edge manipulation tools.
Mesh machine: a set of tool focused on hard surface modeling with out the use of sub division surfaces. It uses chamfers and fillets quite a bit. https://machin3.io/MESHmachine/docs/
Machine3tools: a set of Pie menus and tools to help with modeling and simplifying common blender tasks
https://machin3.io/MACHIN3tools/docs/
Start with machin3tools, It’s inexpensive and easy to get your head around.
Once you know that then get Mesh machine and learn it’s functions. The finally box cutter and hard ops. Keep in mind they are tools sets and really just short cuts for tools that are already in blender. If you don’t understand the basic functions behind them and what they are meant to do they won’t really help very much. By that I mean understanding what it means by marking a edge as sharp, uses of vertex groups etc.
thanks. this guide was what i was looking for