Writing Site Before Publishing

I currently have a well ranked website at newhomevegas.com I want to replace the content of this site with a wordpress blog. I have a hosting account at godaddy. Is there a way to start working on the WP blog and keep the other site up until I’m ready to make the switch? I do not want to have to re-write url’s or cause unneccesary work but do not want to lose the rankings I already have. Is this going to be too complicated? Should I just get a new domain? Thank you for your help.