I would make the recommendation to get your work to host your site, using the domain name you purchase. You will then build it and leave it under construction until you are ready to go live, after all the approvals. You can let those who need to see the site see it through screenshots, or working closely with them. When all is well then you just take the site off from under construction. There are plugins for under construction landing pages.
If you need other help please ask.
