Create a landing page with a simple backend

I need to create a landing page with a form that will collect information from the user and validate a code against the one created in the backend. The details to collect are: Name, Email, Phone, Language and Code On the same page some banners will show up, these banners must be manageable from the backend (add, edit, delete) The design will be provided by another agency, so its only the form, code and backend what is needed here. Functionality is simple, user receives a url and code (out of the scope of this task), he clicks the url and arrives to this landing page we are creating, he faces the form which he fills with his details and the code provided before, if the code matches with one in our db then an email with his details is sent, the details are saved to the db and he is forwarded to another page which will be always the same. If the code doesn't validate he's shown a message. Please provide a budget and timeframe for this to be done. You can use any framework or cms for the task. Best regards, Santiago