Create an application that posts to WordPress and Social Media

We need a webapplication in which we can simply write and save articles. These articles must then be posted to a WordPress blog and sent to different Social Media. This is important: We must be able to add new Social Networks quickly. So perhaps a plugin or modular thing must be created in the application. We absolutely need flexibility. For every Social Network we must be able to define how the post to that network will look like. (like how many characters, image, hashtags, etc..) Some networks uses an API to access (oauth) like Twitter and Facebook. Other networks like Google+ don't have write access with their API yet, so autoposting must be done via username/password for those networks. We must be able to schedule when a new article is being posted to WP and the social media and tehre must be a logging so that we can see if and why a posting failed. Please advice and tell us how much time it will take (approx) and what your price is.