In my industry signing bonuses are paid with the first paycheck but there is a clawback if you voluntarily leave before a year. There's no clawback if they fire you, though.
Clawbacks are effectively bad debt when you’re talking about this type of worker/income bracket. While the language is always put in writing, no employer I’ve worked for would actually attempt a clawback as it’s not worth the bad press/word of mouth when you pull $3000 out of their checking account 2 days before their rent is due.
We also have another kind of bonus that's paid after a year and we don't call it a signing bonus.