What is the first "big" item a shop needs?

A quick thought experiment of sorts.

Let's say you have a permanent garage in which to work on your projects.  It's well lit and comfortable enough to work in year round.  Basic tools and their storage are already taken care of, and there is a good workbench present as well.  Power sources are moer than adequate.  So the essentials are already there.  And let's say the type of work you like to do is Challenge-style car builds.

Out of good fortune (or something) you end up with $500 to spend, and you decide you want to make your first "big" purchase to make the garage a better working shop.  What would that "big" thing be and why?

A nice drill press?  Sheet metal tools like a bending brake?  A small lathe?  A tubing bender?

Welder? If that is already owned how about a plasma cutter?

$200 Air compressor, $100 bench grinder with a wire wheel, $100 worth of three 4.5" grinders (cut off wheel, wire brush cup, flap wheel), and the rest on air tools or a sawzall.

If the air compressor is handled already then add a 220V stick welder and a harbor freight needle gun instead of the compressor and tools.

Big compressor 

My personal order of use, which is not order acquired.

Drill press

Welder

Portaband

Air compressor. 

I think it depends on your other hobbies, how useful the specific tool would be around the house. 

And while you're probably looking for better quality and/or on Craigslist, you could get decent examples of the first 3 for less than $500 combined at harbor freight. Mine have all held up to a year of abuse so far with no problems. 

A good welder, if you're gonna be doing budget builds and will need to fab stuff. $500 will get close to a Hobart Handler or similar.

I'll be honest, I always had wanted a big compressor (I have a small 20-gallon for airing tires), and my garage shop is pretty damn well-equipped. But I have never pulled the trigger on a big compressor for the main reason that......well, I can't think of anything I'd use it for. My cordless (DeWalt) impacts can get any bolt off they've ever had to. I have plenty of electric power tools like grinders, etc that work just fine. I guess if I was going to do bead-blasting, or whole-car painting? Otherwise, in my 10 years with this garage I can think of 1, maybe 2 times I've ever said "wow, I wish I had a big compressor to run xxx tool for this job."

For $500, assuming you already HAVE a welder, I would go:

2 x good angle grinders (one with cutter, one with flap wheel)

jumbo packs of Harbor Freight wire wheels, flap wheels, cutting discs

harbor freight 10- or 20-ton press

harbor freight engine hoist and leverer

Save up more $$$ and get a lift

Lift. LIFT.

LIFT.

While my first thought was "big compressor" I have to admit with the advent of quality cordless tools, a compressor isn't as big a deal as it once was.  I often wish for a welder and will likely be my next shop purchase once I clear out some space for one.

I’m not really shopping for anything at the moment.  This was a scenario that crossed my mind the other day, and I thought it would be very easy to answer.

But I haven’t come up with a good answer yet- even in the context of my own garage.

Since we have folks here that build amazing things with surprisingly little equipment, I was curious to read what others thought.

Eastwood mig w/ the aluminum spool gun for right around $500 if you've got 220v.

Also agree w/ the lift saving if you plan to have vehicles in/out vs. one long term project.

You said basic tools are included, but I'd say cordless impact, grinder, etc.. fall in that category, so if you don't have them, start there.

Another vote for compressor. Maybe a nice 2 stage with hardlines run throughout.

Another vote for welder, but let's say you have that already.  Grinder, sawzall, and drill will take you a very long way with the right attachments, and the cheap corded impact from Harbor Freight is surprisingly powerful.  

The only things I can think of that I haven't seen mentioned at all are an engine hoist and torque wrench- realistically, those things and some attention to detail and cleanliness unlock the ability to do full blown engine builds.

Save the $500 until you can turn it into $1500 and buy a MaxJax-type of lift. They are not super expensive and soooo worth it compared to dealing with floor jacks and stands. 

I have mixed feelings re: hoist. Even in it's collapsed, legs folded up state it takes up a fair amount of room. I'd say you need to know what sort of work you want to be doing in order to prioritize.

Parts washer, pressure washer, etc might make car work a lot more enjoyable..

I'd say compressor.  Once you have it it's useful.  It's good for airing up tires, blowing dust out of places, etc.  And having it makes certain tools cheaper like an impact.  The torque to price and size ratio is quite a bit better for air vs electric in that case.  Grinders and such can be electric though, as there's not much price difference and those require a huge compressor, while impacts and such can get by just fine with something much more modest for an air source.  

I'm looking at spending between 500-750 on a mid rise scissors lift.  For what i do, it'd be perfect.  Just got to find one.

1. MIG welder

2. Pair of angle grinders and a dozen attachments

3. Bench grinder

I got by without an air compressor or lift just fine on my last Challenge build. You can fab a crazy amount of things with just a welder and grinder.

I'd say as far as utility goes, a lift.  No question.  I'd rather have a lift and all hand tools than anything else.  So I'll answer twice because that's half as helpful as a real answer:

General work:

I bought my USA made 2 post lift of Clist for $700 (it's a 1988 model)..   That's also my engine hoist in addition to a host of other things.   I love my big arse compressor, but I'd choose the lift over that no question.  Save up $200 more :)

Fabrication:
I also bought my USA made wire feed mig (1989?) at a swap meet for ~$175.   It uses name brand parts so it's serviceable (tweco gun, for example), and I use the heck out of it.    So if the budget was a strict $500 and I wasn't in a hurry, I'd say budget $3-350 for a good used mig by the time you get a bottle and some wire and a few minor parts and an auto darkening helmet.  Then get two harbor freight angle grinders and a bunch of DeWalt cut off, grinding, flap wheels, etc. Keep one set up with a cutting disc and then do the grinding/finishing with the other.  You'll spend the remaining $50 on clamps and an angle gauge.   Get better angle grinders if you can find them, but the HF ones will work for starters.

What type of work are you wanting to do?  That could help you with your choices. 

I had a bunch of big stuff I've sold-lathe, drill press, welders, sand blast cabinet-when we moved to a larger house with a smaller garage.  I kept the big compressor as I have air tools.  I purchased a MaxJack recently and hope to have it installed soon (need concrete work first).  I most miss my blast cabinet, MIG welder, and drill press. 

Note that many lifts assume you have shop air in order to release the safety catches, so you need to have at least a little compressor in order to use one.

The Bend Paks and Benwills we have at the shop all have mechanical catch releases, FYI.

Having access to a pro shop and my home garage - a lift is not a necessity. I've built three cars from the ground up without one. They're nice to have and my new shop is going to get one, but I've made it this long.

I agree that a welder (with gas) is #1, followed closely by a well-integrated air system and then a bead blaster. I've got a big compressor because I have painted cars, but the oiled compressor is also quieter than the usual cheap 20 gallon oilless and runs less often, so it's more pleasant to be around. Air tools also rule over their electric counterparts.

If you are going to buy a welder, see if you can spend some time with an identical one first. There can be surprising differences. We have a Lincoln ST175 (I think) at the shop and I have a Lincoln 180 at home. Very similar specs but mine is a whole lot more capable for some reason. It'll handle much thicker material and I think it lays down a better bead under all circumstances.

You didn't specifically state "auotmotive" projects, so, I say table saw.

Tools that I have found more use for that I thought.

Multitool belt grinder. I have a friend who is a knife maker I was over there and used it at his shop. It's great for making brackets and parts fabrication. It will remove stock go much faster than a stone. I use it all the time. If you already have a good bench grinder you can buy it cheaper as just the attachment.

Multitool

Portaband and a swag offroad table for it. I use this all the time now to cut stock. I would love to have a big metal bandsaw but this thing has been great for a fairly low cost of entry vs. a 3 to 4k metal bandsaw. 

I use my drill press a ton also. This takes into account I have welders and a plasma cutter already. 

The most used large tool in my shop is by far the compressor. Everything goes faster and easier with air tools. Throw a blast cabinet in the mix and it's even better yet. Get the biggest, belt drive, oiled compressor, you can afford on Craigslist.

Next up would be a welder.