The biggest risk is you get something that is not what you want, are out some money and have to delay the launch.
If you are really concerned about it. A css framework can help your developer eliminate a lot of pain points and make a designers job easier down the road. For example twitter bootstrap is really easy to customize the color scheme, uses a grid layout, and does responsive design. If you don't like bootstrap there are a bunch of other frameworks that do the same thing.
Comments
The biggest risk is you get something that is not what you want, are out some money and have to delay the launch.
If you are really concerned about it. A css framework can help your developer eliminate a lot of pain points and make a designers job easier down the road. For example twitter bootstrap is really easy to customize the color scheme, uses a grid layout, and does responsive design. If you don't like bootstrap there are a bunch of other frameworks that do the same thing.