Awesome news that your venture is almost up and running!!
I have worked with a few businesses like yours previously so I know that they have some unique requirements. As such, I would suggest contacting a local insurance broker so that they can help you get the covers you need and advise you on any potential exposures that you should consider. I would probably avoid buying a policy online as it is harder to get a tailored solution (which would be preferable).
Of course I am happy to answer any general questions that you might have in the forums, otherwise feel free to PM me if you need me to look at anything specifically.