What should I look for while renting a shared office space?

I am starting a business in Bangalore, and am thinking of renting a shared office space or a virtual office space.

Is it possible for me to incorporate a company at the shared office address? And, the virtual office space?

What are the drawbacks of a shared office space?

How are the telephone/utility bills dealt with in such an agreement? Is there anything that I should look to have explicitly included in the rental agreement?

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