[saluki]

You should probably setup a business checking account to deposit your stripe payments in and pay expenses out of.

If you are in the US running your SaaS as a sole proprietorship (get an EIN number from IRS) is ok till your idea is proven and you have a consistent MRR showing continued growth.

Then it's probably time for an LLC consult with an accountant and attorney though before setting anything up.

I wouldn't waste time/effort and expense by setting anything up too early.