Oh, what the heck, I'm gonna chime in here.
I've been doing this now for 30 years myself come 10 days from now when The Cure played Toronto at the SkyDome in July '92. I've owned a sh*t-ton of equipment over the years and this isn't to hi-jack or say one thing is better than an other -- it's more about saying don't do what I did trying to always find the next better option.
For recorders, I started with a loaned AIWA portable recorder before buying an analog Sony D3 pro Walkman, followed by a Sony D7 Portable DAT deck, back to a D3 pro Walkman after my portable DAT suffered a mishap near a mosh pit, a Sharp MD Recorder, an Edirol R-09, a Sony M10, and currently run a Sony A10. I've also owned, for open recording, a Tascam DR-60, DR-70, DR-701, Zoom F4 and currently own a Sound Devices MixPre-6.
For mics, I started with the usual AIWA tie mic, then Sony tie mic, a Sony ECM-909, Core Sound Binaurals, Giant Squid Audio Labs Omnis (yeah, ugh), Sound Professional AT933 (whatever the model was), Church Audio CA-11's and CA-14's (omnis and cards), Church Audio CAFS and DPA 4061's. I then "graduated" to my first low-pro open/007 rig with Naiant AKG Actives with CK63 and CK61 caps (2 sets). I eventually sold all of that and moved to nBob actives with the Naiant power solution and Schoeps MK41 and MK22 caps. After a life changing event around 2014, I sold off my gear the following year but then got the itch again and picked up a set of DPA 4061's with DPA D:Vice (for iPhone recording). Realizing that carrying that wasn't much more different than running nBob actives, I ended going back to an nBob actives set with AKG CK63'w and a Baby nBox (which is where I am today). Somewhere along the lines, I picked up a pair of Line Audio CM3's (which I use for open taping).
So enough about that. I think the point that @daspyknows makes is simple (and several have told me the same thing over the years): buy nice or buy twice.
Granted, you want this to be your "first" shot at this. Maybe spending $2500 today on "top notch" used gear is a little too rich for you. I think back to buying my portable DAT and Core Sound Mics, and those were around $1300-1400 at the time (and that was 27 years ago) -- with inflation, this would be pretty much covering this rig and it's a million times better than what I started with. There are other options, if you can find them, such as the AKG nBob actives with Baby nBox and AKG CK63 capules (which are harder to come by now as they're no longer being manufactured). The AKGs are a little heavier (and larger) than the Schoeps but they're not at all impossible to work with. You might be looking at $1300-1500 instead (which might still be a pretty large outlay).
Crowds pre-Covid were pretty obnoxious but post-Covid is something else. You'll definitely want mics that can reject chatter next to you because it's almost impossible to get away from these days (so you'll need cards or super/wide cards). This is why I would _AVOID_ the DPA 4061 (omnis) as they'll pickup everything around you.
If you want to get your feet wet, look at picking up some CA-14 or AT-843 (SP-CMC-4) Cards with 4.7k mod, with at least a battery box, and a Sony A10 recorder. I love my A10 -- it's small, can be controlled via my iPhone (Everybody has phones out nowadays) and has never let me down. Depending on if you buy new or used, you could be spending about $400-750 on this set up.
To the point a few people have made: with concert tickets costing what they do now, I want the best capture I can make. The full-sized caps will smoke the smaller caps EVERY day.
Where to stand -- not up front. I've had to record some shows in smaller venues from the 3rd or 4th row but I would say somewhere between 50-70% of the way back to the soundboard from the stage is "ideal." Let your ears do the listening and listen for where it sounds the "fullest." I usually use the opener for this and then guess where I need to be for the main show (this is obviously for general admissions shows).
Best of luck!
