How much would it cost to add an addition to a simple bungalow?

We might be thinking of buying a bungalow, but before we do, we wanted to know the cost of extending the house and adding an addition, thus making it a two storey home. The extension would be the back of the house, into the back yard by 5 to 10 feet. The top floor addition would be part of the extension to include 3 bedrooms, 2 to 3 bathrooms and a bonus room. I am thinking the top floor would be 30 feet by 30 feet. Does that make sense?

Hope you could help with my questions. Interested in seeing what quote this may be, as to know if the addition to the house would be affordable or not.

Thank you so much for your help. Looking forward to your answers.