Contao capabilities using an existing HTML5 page

I am not sure whether the following is possible with your product, but if Contao
can do what I have outlined below, then I would like to purchase a commercial version from you
with the required extension(s) to fully complete the task below.

This is for a client I have done some work for in the past. They are a furniture
consignment warehouse where they recently had fraud because employees figured out how
to go around the barcode generation process.

They have a separate barcode and label generating program which I have modified to
output everything into an html5 webpage complete with CSS (if Contao can do this step also, I would be thrilled).

I need to be able to take this existing html5 web page and use it as a template for Contao.

I have a web form which is connected to a SQL database which I am essentially using as
a consignment customer rolodex because it includes all of the consignment customer
inventory items.

I need to figure out a way to do the following with Contao for one customer at a time:

Choose a customer from the database,
Select some of the inventory items with checkboxes, then populate various elements of
the html5 template based on what is selected on the database form.
Create several subdirectories based the inventory item names,
Output a different variation of the html5 webpage into each subdirectory (based on the
inventory item name).

For example, one of the consignment customers only has six items on consignment.
I select four of these items with my form.
I then need a way to create four subdirectories when I submit my form, then have Contao output one variation of the html5 template into each directory.

If Contao can do this, then I could purchase a commercial version.
If you have any examples or snippets of code how to do this, or a way to make this into a simple page of Contao CMS, I would be very grateful.
I am even willing to start from scratch with my database if necessary.
Please let me know which plugins I will need and what my total price will be.
Thanks in advance,
ClaireW