Ask HN: How much sales commission do you pay/get?

I'm currently running a SaaS and I'm starting to look around to hire the first sales rep, so the last few days I've read a lot about creating a sales plan, commissions, base salary and so on.

My curiosity is, for all those who have hired sales people, or sales people themselves, how much do you give/get as commission when a sale is closed? And for how long (in case the product has recurring charges)?

If you want you can also write more how's the structure/plan, if you get leads or if you have to find them, and any other info you think it'd be useful =)