In many cases, $5,000 is going to be pretty much the floor.
You'd be well advised to get a lawyer, and even if everything is absolutely clear cut and cleanly in your favor, you're going to burn up 10+ hours of lawyer time, and that's $2,000 to $5,000 +/-.
If your lawyer is going to have to push the DA to decide that the shooting was righteous or otherwise pitch your position, we're getting up toward $10,000. Throw in a court appearance or two, and now we'd be pushing $15,000 to $20,000.
Now if you're really unlucky and wind up in trial, costs for a jury trial, including private investigator and expert witness fees, will push the bill up to somewhere between $75,000 and $150,000.
You can probably add another $2,000 to $20,000 to the above figures to cover time off work, bail bonds, etc.