Develop Magento extension to integrate with Virtual-POS

We use Magento CE shopping cart, and we need to integrate it with a local Virtual Point of Sale (VPOS). The company responsible of the VPOS states that their solution is capable of being integrated with any shopping cart, within them Magento, but they don't have available any extension, just a technical guide. In the following link you can find the technical guide for the integration. [login to view URL] What we need is the following: *We will give you access to an online develop environment. *Develop an extension/module for Magento that integrates with the VPOS of the given link. *The extension must be given as a "package" for easy installation in our production site - Source code must be given. *Basic installation documentation. *Proper coding with explanation inside each file. *The extension should enable a form in the admin panel to easily update the VPOS parameters. *The VPOS returns "error codes", so this result must be accessible for each transaction from the admin panel. ---- There is already an OpenCart extension for the same VPOS provider, so you can get an idea of what it is and how it works [login to view URL] - of course we do not need the same, this is just a reference of a similar case. --- We are looking in the market for developer quotes, as the VPOS provider states, is easy to integrate, they will provide feedback, and we have seen similar examples of integration, so if you are an experienced Magento developer, this won't take long. As the project is not too complex, and we will give you access to the develop environment, the budget is of a simple project. - Please check the technical guide before bidding, as we need an estimate total cost - If you are awarded project starts on September. Best regards, Santiago