The top 5 most important tools every shop should have

Multiple 10mm sockets 

I say it every time, the best tool ever: A lift. So worth not buying one crappy project car and spending that money on a lift, whether full size or the low-ceiling type like I have. I prefer a two post, but I know folks that get plenty of good use out of a body shop style scissor lift. Anything that helps  you work at a height that offers a more sustainable, more comfortable posture is a good thing.

(1)Battery operated tools. I seldom have to run my compressor unless I need to blow something out, and I don't miss the noise! As my old craftsman stuff dies I am switching to Milwaukee, yes I have m12 & m18 but at least 1 charger does both type batteries. We have a local store that gets returned & overstocked goods from Lowe's and Home Depot great place to find good deals on tools but get your batteries elsewhere. (2)Also bought a used lift about a year ago. Planning on pouring the concrete slab for it under the pole barn this month. (3)Wi-Fi in the shop as the phone signal is poor here and the steel shop is an RF vault. (4)Big fan, torpedo heater. (5)Lots of lighting.

Kroil.  It's not overrated.

Brake parts cleaner

Light (more valuable than heat, even)

Big pipe for cheating

Cable hose clamp pliers 

Powerful impact with tons of extensions and U joints

A word of advice for those who do yard work with an "ecosystem"  I still have 2 battery systems - 1 for mechanics and 1 for the yard..    Love my Bosch but not much for the yard work

One of these for sanding out spotwelds ( on panels that you are NOT going to reuse) and sanding down your welds to make them smooth.

mazdeuce - Seth said:

Bifocal safety glasses. 

Flashlight. 

Hydraulic press. 

I agree with the flashlight. If you can't see what you're working on, it makes things insanely difficult.

Broom and a dustpan. 

I used to tell my apprentice "if you can't use those tools, you're not allowed near anything else".

Can't stand a dirty shop.

How about the Snap-on standard tool box 

Aside from basics like a set of hand tools-

1. Internet for video, data, etc.
2. Electric impact. I have a couple in different sizes
3. Rolling shop stool. Just improving ergonomics was such a huge win
4. Split beam torque wrench. They don't need to be set to zero all the time like the spinny ones.
5. socket versions of most things like allen keys, torx, etc. It saves  do much time over trying to spin something out with L wrenches. snap them on your small impact and go go go.

Is an electric impact worth it over just using wrenches and ratchets? I've got a full wrench and socket set, jack and stands, and various screwdrivers, but that's about it right now. Plan to get a torque wrench, code reader, and a multimeter. Definitely want to do my own work when I get my car, but I'm not entirely sure if an impact is worth it, or if I should spend my money on other stuff. 

hybridmomentspass 

Making templates.

also try manila file folders    especially if bending the template 

A good speaker system / music - nothing less than lamb of god !

Evanuel9 said:

Is an electric impact worth it over just using wrenches and ratchets? I've got a full wrench and socket set, jack and stands, and various screwdrivers, but that's about it right now. Plan to get a torque wrench, code reader, and a multimeter. Definitely want to do my own work when I get my car, but I'm not entirely sure if an impact is worth it, or if I should spend my money on other stuff. 

An impact is a workflow improvement. It isn't a must have to do most things but it makes some tasks easier. With the improvement in electrics I'd probably do a smaller form factor mid torque before I do a big impact. A good breaker bar does the same job a lot of time. 

answering a related question:

What expensive tools should I save up for once I've covered the basics?

The Blue Wrench aka oxy-acetylene torch:

loosens stuck fasteners, brake disks/rotors, pressed parts, rusty fasteners.  bends metal.  straightens metal. cuts metal. welds metal.  hardens (tempers) metal. softens (anneals) metal. shrinks metal.

portable. self-contained....low powered shop, apartment, junk yard, track.

there is no alternative!

Lift

Sandblast cabinet... big

friends endlessly think a blasted part is a new part.  saves $$$.  

mating parts fit.  gaskets don't leak.  paint lasts longer.

big bench grinder, 8 inch, coarse and  fine, on a pedestal.

ditto wire wheels.

when you move on to fabricating, buy a nice used Miller MIG welder.   then try your friend's cheap welder...and thank me.

insulate, heat, cool your shop!!

lastly, like many other tools, once you have a mill and lathe, you'll use them more and more to repair parts, make parts, make tools....that work perfectly.

After having one in my garage for a few months now I want to add mini lathe to the list. I bought it thinking it would be a fun learning tool but I have used it on a few small projects like a thumb screw for my video tripod and I am sure there will be a point where I also get a benchtop mill. 

When starting out, I invested in the entire set vs. buying just the one tool needed for that particular job.

If I needed a 10mm deep well socket, for example, I bought the entire set. Glad I did stuff like that. 

Also, to second like everyone else, battery-powered impact gun. 

Headlamps

torque wrench

cordless 3/8 ratchet

vacuum bleeder

gear wrenches

trans jack

MyMiatas said:

One of these for sanding out spotwelds ( on panels that you are NOT going to reuse) and sanding down your welds to make them smooth.

And grinding the heads off of seized fasteners on things you are trying to pull apart, that are in places not easily accessible with other tools.

Need to remove the fan from a radiator you are replacing but the nuts captivated in the plastic radiator un-captivated?  Get down in there with the finger sander.

David S. Wallens said:

When starting out, I invested in the entire set vs. buying just the one tool needed for that particular job.

If I needed a 10mm deep well socket, for example, I bought the entire set. Glad I did stuff like that. 

I have an entire set of Torx bits bought one at a time. I wish I'd bought the set in the first place.

The most helpful tool that i never knew i needed until i had one is these zip tie (cable tie) pliers! They not only tighten a zip tie much better than i can by hand, they also clip the loose ends off cleanly all in one way motion. :) 

PPE (respirator, safety glasses, muffs, gloves)

Trauma kit/IFAK

Fire Extingusher

Lighting.

Another person.