#1
Let's just make sure that you're adventure into here is not a guide in anyway to build a rig, I just want to build my first one and I have absolutely no idea how. So now that, that is covered let's dive into this.

In my last post I discussed my tragedy of ripping the strap button out of my guitar you can find that discussion here (https://goo.gl/4R0azo) if you are interested. 

But today I'm going to tackle the beast of building my first guitar rig. I have watched a few videos and picked up enough to know that I need a black and silver box, a power supply (surge protector?) and then all the rest. I also know that I need a amp head or an Axe FX but sense this is my first rig I don't really want to drop 2k on a new Axe FX. So can we try and keep that out of the picture? I want a rig that will be as simple as John Petrucci's, but small enough I can fit it in the back seat of my 2008 Subaru Impreza. So yeah, thanks for stopping by and if you have any information that will help me or maybe a link to a "Perfect guitar rig building" thread on Pintrist please give me that link. 
#2
You might get better responses over on the GG&A thread and hopefully a mod moves it, but in the meantime:
Budget?
Style?
New or Used?
Current gear?
Gibson LP traditional and DC standard, SG standard, MIA Standard Strat, Schecter Banshee 7
EVH 5153, Orange TV50H 2-2x12's
Line 6 M13
#5
After you have a great guitar, here's what you consider

1. Get a great amp. Yes AxeFX is great but its pricey and you'll have nothing left for others things. I recommend Eleven Rack. I had it twice already and it never fails to help me forget the AxeFX. But getting a amp like that assumes you have a sound system. If you don't then a combo amp may sound like a better deal for you. Really what I find its important is the basic tone of the amp and if it faciliate playing dynamics. So a tube amp may be the way to go but its hard to maintain so I'll go for the next best thing an amp emulator. I'm bias on the old Peavey Bandit series. It emulates tube greatly.

2. Get a sturdy effects board with great power supply. A pedal train board is great to protect your pedal investments. Don't skim on good power supply. Get reputated brands like Voodoo Labs or T-Rex. I've been saved so many times by good stable power supply that I'll vouch for it.

3. A Looper pedal. Yes yes yes, everyone needs a good looper pedal because its all about the groove. If you can't get this right, you can get anything right. It's the most essential pedal ever.... https://playgoodguitar.com/best-looper-pedal

4. Cables. Yes get good quality ones. Forget those patch colourful ones with low quality connectors. Neutrik connectors & Canare/Belden cables?

5. A good amp in the budget you have usually don't come with great distortions so the next thing to look into is a distortion pedal. Go crazy shopping for one of these. It's lots of fun because it'll determine the kind of tone you have. There are other essential pedals like reverbs and compressors but not all are needed.
Anyway I've written an article IF YOU CAN ONLY HAVE 3 PEDALS. https://playgoodguitar.com/if-i-could-only-have-3-guitar-pedals, hope that'll help and may save you a bit of money.

I'm so excited for you. Building your first rig is like being in a romantic relationship, you have no choice but be excited about it. If you have more specific questions, don't hesitate to contact me. 

HT
#6
Tube technology is something like 80 years old. Guitar speakers are limited range systems and cabinets are large, heavier than they need to be and can be emulated. Buying one-trick pedals can cost you more than an amp. 

The short of it is, a modeler, a power amp and a full range speaker cabinet can be lighter, louder and more compact, and can provide you with an extremely wide range of choices, and can be used over a wider range of operational venues from bedroom to arena. And it easily adapts to recording.

One option is a used HD500X and a powered speaker system like the Carvin PM15A (https://carvinaudio.com/products/pm15a-molded-active-main-monitor-speaker ). The PM15A couples a 15" LF driver and a 1.5" Titanium HF driver with a 400W RMS built-in amplifier to produce a speaker that weighs 38 lbs, measures just 18" wide X 14" deep X 28" high. It can be placed on the floor, on a tilting amp stand or even on a speaker pole (the pole attachment is built in). The HD500x replaces foot pedals, amp preamps, cabinet styles. It mostly eliminates a whole bunch of fiddly bits including pedal connecting cables, power supplies and/or batteries, separate expression/volume/wah pedals and it allows you to save settings in user presets. 

Another option might be a Line 6 Helix with a lightweight power amp and a three-way speaker. I'm using a nine-pound 1500W power amp and a 50-lb speaker that will handle 800-900W (the power amp automatically adjusts to this power level based on speaker impedance). And it will all still fit into the Subie.