How to and how much to devalue the flood zone property?

[Amit Shah]

I signed a contract for buying a mixed use property and realize that the property is in AE flood zone. Can anyone have an idea as to how to devalue the property? Any calculations to use. 

The seller is saying that the property did not had any flood in last 20 years. But i am trying to understand the pros and cons of buying a flood zone mixed use property having 2 apartments and 2 studio office units.