I've been working with DNN since 2003, so I'm sure I can complete this project.
To clarify things. The DNN framework separates the theme or "skin" as it is called in DNN from the functionality and, content of the site.
The administrator can create and edit pages using the Site Administration pages.
Functionality is added to pages by adding a module to a page. The type of functionality needed will dictate which module to use i..e the "texthtml" module for text/html content or the "gallery" module for a portfolio page. Modules are placed in a "pane" on the page, panes are defined by the layout of the skin.
The content is then added to the module.
Almost everything described above is stored in the DNN database except for the skin / layout which is written in either C# or Visual Basic .NET
The fastest, simplest and, most reliable way to complete this project would bee to shop around for a prepackaged DNN skin then, have it tailored to suit your needs. Most skin vendors will do the customization for a reasonable fee, typically the cost of the skin and customization will be about $100 AUD Usually a prepackaged DNN skin will also be responsive so it will also support mobile devices
If you could send me a site map with a description of the functionality required I can come up with an accurate price and time frame. Quite frankly $1500 AUD sounds high, I can probably do much better.
Regards,
John H. ward, Jr.