Creating CCK extension with advanced search

The request is for a fully native Joomla! 1.5 extension (MVC) that has the following features: Categories: Unlimited levels of categories, each category can have unlimited number of parents (i.e. category Laptops is under the categories Dell and Acer at the same time). Types: There should be different types of items, each one would have different fields. Fields: Fields to be assigned to types, a minimum field types would be: text, textarea, htmltext (WYSIWYG), select (dropdown), multiple select, radio, checkbox, video (parsing youtube and other providers URLS), file upload (attachments), image (a single image for the item), images (gallery), link, email, calendar (date with JS calendar picker), telephone, tags. Different validations should exist for each field type. There should be no hardcoded fields in any type (i.e. no title or description hardcoded). Crucial requirement: relations between fields must be available (i.e. after selection of Country from a dropdown or multiple select another dropdown or multiple select should list only the cities from that country - this is just an example, we need this feature as a generally available for many fields). Any field should have the possibility to be linked and dependent to another. These actions should apply both on submit and advanced search. Another crucial recuirement: Admin should be able to set with lists (i.e. checkboxes, select, multiple select) to be extendable by submitters (i.e. when users submits new item and his country is not in the country list /either checkboxes, select, select multiple/, he/she should be able to add new value, which is saved and showed as part of the list on the next submit). Advanced search: Should be like follows (field type-> field view on advanced search): text -> text textarea-> text htmltext-> text select -> select (with dependancies on other fields if such exist) multiple select-> multiple select (with dependancies on other fields if such exist) radio->radio checkbox->checkbox (with dependancies on other fields if such exist) video -> yes/no checkbox files -> yes/no checkbox image -> yes/no checkbox phone -> yes/no checkbox calendar -> two options at the same time. The end user should select each to use. Either a date is withing a range or it is exact (i.e. date between 1/3/2009 and 3/3/2009 or exactly 1/3/2009 Any field should have the following attributes: wheter to be displayed in category view, item view, if it is advanced searchable, if it is simply searchable. Items: Items should be associated with a single type, but should be in multiply categories. Items should have the option to be featured or not. Other requirements (admin should be able to switch all on/off): front end users should be able to comment items(ajax), rate items (ajax), add items to favourites (ajax), view their favourites, submit items (if having the right access), report items to admin (ajax). Views: Minimum required views are: category view (single or multiple), item view, advanced search view, featured items (from all or selected categories), type view (all items from specific type), add item layout, top rated, most commented, most rated, favourite, Access level: should be in the settings of the extension, admin should be able to select who could submit Modules: Latest comments, top rated, top favoured, most rated, newest, most commented. Plugins: Best is if fields are done through the builtin Joomla! plugin system. I.e. each field type is different plugin, so the extension could be extended in future. It is required to have a search plugin. Features like comments, rating, favouring etc. could also be done through the plugin system (recommended). Most of the features can be seen in Mosets Tree, K2, but not with that much power. A detailed (more detailed than above) document with all requirements will be sent upon agreement with selected vendor.