Adapting a directory WP theme - mainly CSS + some development

Hello everybody, We are currently building a webdirectory for companies in a developping country. The project is based on the wordpress theme Listify. Few words regarding the website : - It is a directory split in 4 main categories (called "Types") - Users can sign up / log in > Post free listings - Free Listings are approved by Admin before becoming visible on the website - Once the listing is approved, the user cannot modify it anymore. He has to contact administration to do so - Premium listings presents more details (pictures, videos etc.) and cannot be edited without admin access. - Users can comments + review + add to favorite - Digital item shopping - Booking only feature The listify them does almost all these features. However, we would like to adapt the them for the following features : 1. Adapt the CSS We would like to create a bunch of new classess to adapt the CSS. First, we would like to add hovers. Then, we would like some elements of the design to be adapted according to the primary class. For example, the header and the hovers becomes yellow in the primary section "Type A"; etc. 2. Adapt the Mega Menu : Actually, the mega menu displays only the "Listings Category" taxonomy. We would like it to work as follows : 1.1 Link "listing categories" to "listing types" 1.2 Display "listing types" in the secondary menu 1.3 Display listing categories related to listing types in the mega menu Hence, the mega menu is not limited to one item in the secondary menu. Instead, it would be extended to the listing types displayed. 3. Refine "featured listings" and other widgets As we would like to segregate our web directory in 4 primary sections, we would like to have a refined "featured listings" adapted to each primary section. The primary sections are defined by the "listing types". For example, for the widget "featured listings" in the main page of the primary section "Type A", only listings related to "Type A" will be shown. A solution to do that would be to create multiple sub-domains. Hence, for type A, we would have a mini-website : [login to view URL] The problem with this solution is : - We do not want users to re-log-in in each mini-website - We want to be able to show all data in the map page What we are looking for : - A concret and cost-effective solution to reach our goals - A partner that is willing to make these changes, provide strong and clear documentation, and follows us after the launch of the website Please indicate in your bid if you are able to do point 1, 2, 3 or the 3 of them. Thank you in advance !