Looking for guidance on best practice in creating a new Wordpress website, online, when
A) I'll be hosting the site on a new server B) The site will need to be viewed by client online C) The site domain is currently live, in use and must remain directed to current server (until site complete) and D) Current site is very old and would likely throw up endless issues if transferred to the new server. E) No-one has access to the current server.
I'm currently looking at options around temp URL's, or just using a dev URL I use solely for builds. Then once complete and DNS redirected to the new server, Find and Replace all references of dev URL for the correct URL.
I've searched online but generally, only find answers to the queries "building site without impacting live site" or "building site locally". Not my query - "building a site online with a domain I can't use as it's in use etc".
Any guidance on this would be appreciated. Thank you.