I've found that the most important thing to do is get a relationship with a business banker. We use Wells Fargo, and maybe I just got lucky, but I managed to find a business banker who I connected with really well and he was able to coach me through everything. Also their phone support has been very good, so on the whole I can recommend Wells Fargo.

Getting the bank account actually set up is very easy, and the business banker will recommend the right plan for you based on your needs as a startup. It only took an hour or so to actually get the account set up, and that part was easy.

The hard part used to be getting a merchant account, and then finding a payment gateway, and then connecting that with a billing system etc, but now that problem has been solved thanks to Stripe. I recently launched a startup that had a full subscription system built upon Stripe and was able to take payments within just a couple of days thanks to Stripe's amazing portal, documentation, and the many open source libraries that connect you to their API.

I hope that helps.