A reasonable fee for live recording

There are....as you said....lots of factors.  Not that you haven't thought of them all...but I'll list a few to get the juices flowin'.

What your local market will bear will obviously determine what you can charge.  No matter how good you are....most bands are really, really broke.

Then, there's the whole dynamic of having to deal with the live sound guy.  Is he cool?  Is he easy to work with?  Does HE already run live mixes off of the FOH board to a CD burner for a fee?  If he does, obviously, you're getting into his pocket.....usually ensuring he's not cool and not easy to work with.

I don't record live gigs much any more.  But when I do, it's special occasions for bands that "get it" on how to capture a great live performance.  Dealing with bleed issues and all that, just throwing up mics in a venue usually leads to mediocre results if it's not planned properly.

And to plan properly, it will cost a bit of time as well as money on your part well before the fact.  Things to consider and buy before hand:

1:  Are you SURE you want to do it?

2:  Are you REALLY SURE?  :)

3:   Think about the club owners, promoters, and sound guys you know from your days playing the clubs.  Now....are you SURE you're SURE?  ;)

4:  How will you mic things?  Will you run your own mics...so that everything is double-miked?  Or, will you purchase mic splitters so that you can share the mics with the FOH guy?  If you're splitting, will you supply the mics - or will the FOH guy?  If you're splitting, will you supply the FOH guy with a snake that goes from your splitters to his snake box?  Who's supplying mic stands, etc.  It can be a reall bugger if you don't have the stands necessary to get correct mic placement....or the wrong mic clips, etc. 

5:  If you're running your own cables, I would suggest you have a giant pile of red, purple, green, pink...whatever color besides black....mic cables so that you can tell which ones are yours and which ones belong to the house.

6:  What are your plans to control bleed in drum OH's?  In-ear monitors?  Will you have a plexi box around the drummer to control bleed from the on-stage amps and monitors?  What about drum bleed into the guitar and bass mics?  SOME bleed is not a bad thing....but too much can take the mix completely out of your hands later.

7:  What's you'r plan for vocals?  Keep the live ones?  Know going in that unless there is extremely low stage volume, bleed from amps and monitors can make getting a good vocal pretty tough.  Live stage bleed is usually REALLY loud.  AND...most lead vocalists are directly in front of the drummer with a mic pointing straight at the drums.  Without a plexi cage around the drummer....look out.  BTW:  No matter what you do, splitting vocal mics with FOH is absolutley necessary if you plan to record the vocals live.  You obviously can't double-mic a vocal.  Well...you could....but it's probably not realistic.

8:  How do you plan to monitor the live show?

9:  Are you going to mic the audience and mix that in as well?  Don't forget long cables for that.

10:  Do you have a backup system in case the one you're using goes tits up?  Sure would suck to haul all that gear and then have to haul it back home for free.

11:  Get paid at least half up front...you want everyone with skin in the game or you'll get taken advantage of.

I dunno...just a few things that come to mind at this particular second.

As far as how much can you charge?  Again...obviously depends on your area - and many times the particular band.

For me, there is a certain dollar figure that it takes to even get me to pack my stuff up and go to the venue.  That figure may be lower or higher to you.  Mine is pretty high...but it helps to weed out the guys who aren't very serious about it.

Wow - you give a lot to think about......thanks.  To tell you a short story of my first attempt at this it went very easy and tracks came out better than expected - so I think I was badly spoiled.  The venue was a restaurant/grill/bar. The band's sound guy was the lead guitarist who does a good mix through a Peavey board. His amp was miked at the grill (a flat profile mic that rested directly on the grill ). THe drummer had two basses with holes cut in the front for mics to go in, and his vocal was miked, which picked up nicely on the cymbals. All I did was was tap off the Peavey headphone jack - to my interface- to my laptop. The audience sound was very minimal, and just enough when they finished each song. Almost all songs came out very clean, well mixed with no clipping at all. So all and all this was simple in this case and with some tweaking on my DAW days later - job done. They were pleased, and this was a "free" one for a friend. But I can imagine other scenarios as you mentioned that would certainly not go this easy and your advice gives me A LOT to think about if I want to dive further into this.........do I really want to ??? not sure.
 
Thanks !

   The bottom line is you may get heart broke. Your joy, desire and
excitement of doing so is a wonderful thing. But it will in many or
most cases be met with you being considered everything from
In the way, to many other negative aspects.

  I've been the sound man where the guy wants to come in
and use my track line outs to record his multi tracks to later
do his own mix and I always do my best to accommodate them.
And I've always been treated with respect. However in those
cases (he) (they) already knew that they could (tap in) so to
speak into my (house board) and I actualy enjoyed the
challenges of (getting him what he wanted).

  (If) however one coming in to do the same thing and totally
disrupting (they're world) can get very offensive to them.
I guess what I'm saying is that if you can go in and get your
tracks by (not) disrupting anything then you may have some
fun and maybe learn something (whatever that is).

  In most cases unless there is some (purpose) such as
for lack of better words (big time) recording of such a
performance or vinue, or desire from the group, artist
performance etc all the efforts in doing so are (can be)
mostly in vain.

  You might want to just try your thoughts and ideas
and see how it turns out. Just know when to realize
that things are not advantageous to the (cause) or lack
of it. People (can) be finicky. My main (thing) is being
a guitar player but I got tired of the whole club scene.
(playing guitar)
 
   Having been a person who likes many aspects of
writing, mixing, etc I was later asked to (run sound)
for a band. The whole set up was ridiculous. We had to
Run our own 125 amp service by taping into the main
service of the building. Power and equipment out the
yin yang. Lights, 48 channels of mixing and two racks
of gear for the mains and monitors.

  It took about at least 5 hours of set up and break down
to do a 4 hour night of them playing. Well I finaly told
them I couldn't take running sound any longer too.
The thing is the group knew that i was unhappy with
playing guitar and just tired of it all and did ask if
I'd do the sound thing and I said (yes) (for a while).

  The reason for me saying all this is that whether
it's The things the OP mentions or the things I've
spoke about (in my case) it came to the question
of (what have I accomplished?). That does bring
the (money) subject into play (for me).

  One must really enjoy doing what they do, or
the money had better be good. 

 

  
 

FWIW: I'd start out extremely cheap or free just to learn it ... and get a 'finished' (though not perfect) recording sketch/video ... with the knowledge you have. 

Or record for 'yourself' ... then keep the recording/video ... for your own collection until 'they 'buy'.