Thanks for asking.
I see that you have purchased X and Pro Theme both. Please note that X Theme is sold via Themeforest and we fall under there pricing guidelines. However, I do see that you have Pro Theme. For Pro Theme we have offers running on bulk purchase. For more information, please take a look at following page:
Coming to the second question. Yes, the validation should work fine using the URL you have shared. You can use the staging to validate the website URL till the time website is in development process. Once the website development is over, you can move the website to production environment from staging. For more information on validation, please take a look at following article.