sounds like you don't trust whoever you spoke with - go with your gut and move along. You need great lawyers and accountants behind you but there are plenty out there that don't remotely get canadian start up land. The answer to your question is they are trying to understand your setup and those questions are totally fair game as its all related to tax etc.

In interviewing accounting firms for my coaching practice, I asked a series of questions about how they do business, who their best accountant would be for my type of business etc.

The key here is to build a relationship with the accountant as well as the firm. Simply going by recommendation without seeing if you are a good fit can lead to issues (I know, I have been there!) You will need to feel comfortable asking questions, seeking advice and input into the business. An accountant can be a helpful advisor if you have a good foundation. The question about proprietary information should then become a non-issue.

I would be happy to role-play this interview/conversation with you and discuss any other follow up questions you may have.

Good question.

Not many questions need to be asked when it comes to accounting. Accountants really need two things: access to your accounting software for the general ledger, and access to copies of your bank statements.

They can figure out almost everything they need to with those two pieces of information.

In terms of keeping things proprietary, there's not much we withhold. They obviously need to know all the numbers to be able to work with you, and it can be helpful to keep them apprised of strategic plans, so they can advise on cash flow if they know it may be tight in the future.