Basic website fine-tuning before we launch

We're about to launch a Hosting website We need some basic fine tuning to ensure the website is completely functional before we go live later this month. We require someone to help with the following four things: 1) Email - ensure our automatic emails will work (so the website will send out vouchers, user account passwords etc on its own). [we have already set up email addresses and the script has been built for these to function etc] 2) Cron Jobs - ensure our cron jobs have been set up properly as they don't seem to be working. 3) Facebook log in app - we have tried to configure the Facebook log-in App but it doesn't appear to be working. 4) Add some basic SEO to our website to make it show up on Google. 5) For billing we are planning to use WHMCS. So I want you to integrate WMHCS theme with my current website theme. Let me know if you have any questions.