Create A Sud-domain Builder Form & Secure Registration

Hello, I require a form to be built pretty similar to the one found on the Wordpress homepage where the user enters in the subdomain they want and once it registers (checks to see if it already exists first) they will be taken to a register form. Here they will fill out necessary registration details and once they click confirm they will be taken to their new site. This new subdomain can only be accessed by the registered user so it needs to be password protected and also load up a standard template which displays some of their registration details like name. This is the start of a large project and this is just a small job. I would like to work with someone on different elements moving forward. To bid please ensure you put PROJECT in your bid description. I will delete automated bids. As I said this is a small stage of the project so budget isn't big. Thanks, Andy