ASP.NET Web Portal Security Check/Fix

The project is build in VB.NET/ASP.NET It's a WEB Application were lots of users are going to make use of. The WEB Application connects through a ODBC to an MSAccess database and retrieves confidential information from here. After having the project finished I want to be sure that there are no security breaches in this web script (mostly regarding the connection to the database) For example: we found one regarding a [login to view URL] breach (maybe there are many more). I need a person that can do a total check on the website itself and secure the connection to the database (which is most important). After finishing this security check, the freelancer has to give me a full report in how to repair those security breaches (if any). Of course the person assigned to this project needs more information regarding the Website itself; we will discuss this after this person is assigned to the project. This all has to be done on short notice. The budget is discussable. Thanks, Patrick Peeters Jabbit Services B.V