There are four levels of pricing to choose from and they are based on the number of invoices you need to send each month. You can learn more about pricing here scroll down to see more FAQs directly related to pricing.
NOTE: if you choose a subscription level like Sole Proprietor that allows 30 invoices a month and you end up sending 50 within your billing cycle you will be automatically moved to the next subscription level, in this case, it would be Small Business with 100 invoices per month. You will remain in this tier – if you want to move back to the Sole Proprietor subscription you will need to manually make this change in your settings.