Your profit margins depend on the price you charge your customers and your applicable volume tier. Here are some typical examples at the entry tier ($1.99 per active account per month):
If you charge $5.99/month per customer: - Your cost: $1.99 - Your profit: $4.00 per customer per month - Margin: about 67%
If you charge $9.99/month per customer: - Your cost: $1.99 - Your profit: $8.00 per customer per month - Margin: about 80%
From 1,000 active accounts your cost drops to $0.99 per account, and it keeps dropping across higher tiers (down to $0.79 at 250,000+ active accounts), so your margin improves as you grow.
You set your own prices — there are no restrictions. Many partners also offer annual plans at a discount (e.g., $49.99/year) to improve customer retention and cash flow.