[enduser]

I maintain an S Corporation for my freelance work and take care of all of the corporate accounting and payroll with GNUCash. The documentation that comes with it is enough to get up and running, and the direct interface to double-entry bookkeeping may come a bit more naturally to a hacker than using QuickBooks.

For a startup, this can save you thousands of dollars in accounting fees, and it helps for at least one active business partner to have a clear picture of the company's finances. Your finances won't be that complicated initially, and the IRS publishes timely guides to current tax law that can usually be grokked in less than 15 minutes. It is trivial to transfer from GNUCash to software like TurboTax Business, which will keep you from making mistakes on the tax forms.

A tax professional should be able to advise you on business forms and all of the filings required for your business form. You could set up a one-time consultation if you don't wish to learn enough to make the correct determination.

Of course if you don't trust each other that is a different story..