To be safe I wouldn't accept payments yet. I would develop your SaaS app on your own until you are cleared to work, then look at accepting payments through Stripe once you get a bank account. You have plenty to do before accepting payments.

Use this time to build out the initial version of the app and talk to potential customers to validate your idea by signing up for free to test out the app. Once you're cleared to work you can approach them to sign up/pay.

Check out http://startupsfortherestofus.com, listen to all their episodes.

Good luck.