[wj]

Depends on your needs. Wave Accounting has a free tier that you could probably use. I tried it out but went back to GnuCash (also use Quickbooks for the day job) as my brain works better with double entry accounting. With Wave (or other online accounting systems) it is easy for both you and your neighbor to track information. You could also do the same with a simple shared spreadsheet.

I would recommend one of you take the responsibility for the accounting and provide the other with monthly income statements and balance sheets.

Come tax time it might be worth your time to hire somebody to do your taxes. Maybe the same person who helped you file your business paperwork since they are already familiar with your company structure.

It isn't accounting software (but it does do income and expense tracking) but if you're interested I'm just about ready for beta testers for some software I've been working on. startopz.com.

Send me an email (in my profile) and mention this post if you're interested in trying it out.