I would not know why would anybody wish to give their accounting information to any online company, distant, unknown.

So people don't do it.

Imagine, your own accountant knows everything about you. Hyr knows your suppliers and your buyers, he has close insight in your business. And you need to be careful with him.

Best is if you can handle your accounting yourself. There is free software for that like https://www.gnucash.org and others. There is also online free software, which you can install on your intranet.

Do not install your accounting online. Internet is not for doing your private business.

And do not give your accounting data to anybody online.

Come back to basics and keep your business private!