Once everything technical is said and done and we have a product to go live with, should we contact a lawyer? What kind of protection do we need from the "rotten eggs" out there? I know we need a TOS and a Privacy Policy (which can be made via templating), but what else is necessary?
If it matters, we're based in Canada.
While not strictly necessary I would strongly recommend having a legal "Check up" with a good lawyer before launching. They can take a look at your business plan and point out any potential pitfalls that need addressing. Half an hour of a lawyers time now can save you thousands later on.
Every company is different, so coming up with a standard set of questions isn't really a great approach.
Recall that the main purpose of talking with the lawyer is to help reduce the number of ways you could wind up in court, either because somebody sued you or because the government decided that you were doing something criminally wrong. So, the main question to ask yourself is "If everything went wrong, how would people be hurt?" Then, think about what government approvals you'd need. Those two things should help guide your discussion with your lawyer. That will necessarily deal with things like your terms of service and privacy policy.