Hello,
i am Cyril from appslabz, we are a Magento expert copmpany.
As you asked to say why we are the best to take this project- we are one of the best team who can give you the best magento solution.
We have dedicated team for each project, we keep our communication with client very regular for the updates and feed back.
I suggest Magento for your e-commerce store, we can bring bet in class design for your website and we can take up any kind of customization you require with in Magento. I have gone through the doc you attached, the requirement is fine and clear.
We can also provide you responsive design, which bring the site best in mobile devices.
Feel free to contact us to discuss further on the project.
Regards,
Cyril