SEO LocalHost Site > Server

[ Moderator note: moved to Fixing WordPress. ]

I’m developing a new website for my domain on my computer “localhost” and I have a concern about the SEO or my existing Google ranking. The old site has been up for a year and while the ranking may not be great, I nevertheless don’t want to lose any position I have when I upload the new version to the server. Am I worrying needlessly or is there anything I should be aware of?

Thank you