SMTP Emailer set up on Windows VPS

We are looking to set up an email server on our windows 2008 R2 64bit vps. We will be sending out over 5000 emails per day and already have an emailer software installed which now just requires a SMTP server to send the mails. We have been using a Gmail smtp server however it is restrictive with the amount of emails it will send per day hence why we are looking to resolve this issue and be able to send at least 5000 emails per day. We use proxies through our mailer however we would like every possible security and anonymity measure in place to avoid any interruptions or inconvenience to our vps provider. Please put your suggestions to us along with your bid and timescales. Once the server is set up we will test it using 1000 emails from our database. Following sending the job will be marked as complete. We will require a lot of other SEO work using this server and also our other servers so please only apply if you are confident in your ability and knowledge. We will have much more work for you in the future if a good job is carried out. Kindest regards