Ajax form for Joomla with DB

Project Description:
I need a ajax form for joomla. I want that this form is only accessible for registered users and that when it is sent that the registerd user information is sent together with the form values.

The form must also be stored, so that the regisred user can check back and see what he filled out at the user menu.
He also may have more then one of these form stored. So the form should be stored with a title for each as for example: "inventory 1" inventory 2"... and each of these saved forms may also be changed/updated.

The Ajax functionality is for a specific reason:

I'll be asking in the form something like that:

How many lavatories do you have? ___

The user will type a number. If he types "3" , three text-field shoul load below:

Please specify the location of each lavatory:
______
______
______


This same structure will repeat several times at the form.

Also I need the form to have page breaks (about six):
Step one... Next button; Step two... Next button..... Finish and Send

It would be nice that someone would create for me a pattern for that so I can change and edit the form easily. I have facileforms installed in my system, so if you want to work with that I am ok.