Who is doing it? Where do they live on the globe? What is their experience? Is this for exclusive rights?

Think about your project. Being realistic (read: probably higher numbers than you want) how many hours are they going to be spending on the project?

Multiply how much they cost (which varies by location and experience and exclusivity) by how much time it takes.

Is it a fast job of 60 hours, and they're a student so you're paying $10/hr? That's $600.

Is it a job requiring a few iterations taking around 300 hours (about 2 months) and they are experienced professional contract artists so you're paying around $40/hr? That's $12,000.

Are they working in a third world country, working fast, and the art will be reused non-exclusively? Maybe 90 x $3 = $270.

If you think about allocating money to ALL different parts of your projects, and not just the areas where you lack skills, don't forget marketing. Of course, if you are proficient in that yourself, or have a great strategy for it already that doesn't need a budget, forget about my advice, but else:

Most money seems to be spent on marketing for the big releases, so if you have a budget for your game, maybe look into how money might improve your marketing strategy. No point in pumping money into creating the best game ever, if you cannot promote it properly later.

General ballparks from my experience:

Music - $200 per track for a professional C-list music composer. $3000 per track for Jeremy Soule or Inon Zur.

Sound effects - $20 per sound effect.

Voice acting - $400 per hour for a professional VA (without a big name). With a big name, likely much more.

Of course, it depends on the people and project's scale. Marginal costs tend to decrease when a project's scale increases.

What is a ballpark estimate for the cost of a single playable character animated in something like spriter?

A lot comes into this:

- Creating the original (2D?) art. What's the art style? resolution?

- Animating the 2D character. How many directions? How many frames? Is this a bipedal creature?

- What do you mean by playable? Just walking around? Is combat involved? Ranged or Melee? etc.

What percentage was spent on art, animation, music, sounds and other assets?

I'm afraid there is no constant for this here. I'm assuming you're doing the art yourself?

Typically, art will take more than music and sounds (unless this is a music-centric game).

Art will be composed of all UI assets and characters. As you pointed out, some of that art will be animated. You will most likely also have "animation-only" artwork (Visual Effects otherwise known as FX).

There is a lot to making a game, and the level of polish is more than a mere variable, it's the entire project. You could get away with moving dots on the screen, and that will cost you nothing. I'm guessing that's not what you mean here.

You should know that scoping a project is a producer's role. It's what I, and a bunch of others, do for a living. A bunch of indie developers learn the hard way that they also need to "produce" and it takes a significant portion of their time away from other tasks. It takes planning, and more often than not, the only way not to fall into a trap is to have experience doing this.

Here are your choices:

- Fall into a trap and learn: If you want to learn to do it yourself, you need to try. Put less money at stake, see where it gets you, learn from the experience, and then use some of the money you saved and try again until you get better at it.

- Learn from others' mistakes: Land a job as a project coordinator, assistant producer or project manager in any video game company. Learn everything you can. See where the business succeeds, and where it fails. Even though it isn't your money, you can still learn from it, better yet, you might even get to choose how to do it and learn from it while not losing any of your own hard-earned money.

- Hire someone: A lot of indies would rather spend their time doing the game and don't necessarily have the skills or experience to plan ahead. There's no shame in hiring an acting producer (in fact, I do a pretty decent living freelancing as a producer/jack of all trades for indie businesses). Meet with someone, describe your needs, tell them your budget, and see if he can come up with a plan that makes sense to you. Most likely, this will lead to a discussion where you are willing to make concessions you didn't know you could do in the first place, and help the person steer the project in the right direction. That way, you can end "on-budget" and "finish" something.

Best of luck!