Access Laptop without password?

I have a friend who has a 14 year old kid whom they believe is engaged in some devious behavior. They have asked me if it would be possible to get into, at least, a guest account on the laptop. They purchased the laptop, but the kid set the password and she cannot get in. Are there any work arounds, in the bios possibly, to be able to get around the password? They actually offered me a decent fee if I was able to even get them able to log on as gues, but I assusme you need to actually get in first, to set up another user account.

I appreciate the response!