Online Secure Database

I own and run an information management company in England. We are currently looking to expand in to a similar market and in order to this we need a web designer to design, build and upload a website as well as providing a domain name and hosting package.

So here is what I am looking for. I have a spreadsheet of information (inc names, addresses, postcodes and client reference numbers). I am looking to make this information available on the internet, however I need to restrict who can view the information and secure the internet connection on which they are viewing the information.

Therefore I am looking for someone to build a website which is secured by an SSL certificate and has a function where preregistered users can login to the site and search on either client reference, or postcode and property number. Once the user clicks search, the website searches the excel spreadsheet and returns the results on a secure internet page.

I would ideally like an admin function so that I can update the excel spreadsheet offline and upload it, but also so I can add and withdraw users. The preregistered users should have view only access so they cannot change the excel spreadsheet.

Can this be done if so what would it cost?