I am working on this non-profit org website. Their current domain name is registered in the name of the guy who is no longer associated with the organization. The domain name is going to expire in couple of months. We have registered for a new domain name. It will be up in couple of weeks as soon as I am done working on the website.
My question is, the current website is #1 on google for a couple of search terms. What can I do to retain the high page rank after we switch over to the new domain name/new server?