Customise Wordpress Geo Directory Place listings

We have a WordPress Geo Directory based website and we have the following requirement for Customisation. Typically customers come to the site and place their own listing. However, the site owner also wants to create listings on behalf of his customers but he needs their approval before they are published to the site. Currently with Geo Directory you can't preview Listings using the WP standard preview option. Here's the ideal scenario: 1. The site owner creates a listing via WP Admin (rather than as a customer using the site to add their own listing). 2. The Client can save listing as a Draft. 3. The Client can share the Draft listing with his customer. The Client either copies preview link and sends email or preferably though WP Admin has the option to send link. Potential: The Draft listing has an expiry date. Only lasts for up to 24 hours. As with point 3. if the preview can be sent through WP Admin, option to have a templated email rather than our client having to manually create an email. If possible when the customer views the preview of their listing if they like it then the ability to approve it so that it goes live - this is desirable rather than a requirement. We can provide access to a dev version of the site, WP Admin etc. We'd need any custom code documented for reference and once approved any changes pushed to the live site. Thanks