If we say about some store site - it is possible.

if we say about sites like amazon - you will need as small 1 - 2 developers in support team

serious site ask:
- serious hosting
- serious support
- serious advertisment
and Joomla as start is very good solution.

Now on OS CCK website Builder you may create:
- any catalog website (car, book, houses ...)
- any content access website(documents, video, files, content)
- any rent/booking website (car, book, houses ...)
- any shop website(real goods or software)
- any CRM website, but because we think there are will need many Print and PDF reports - we now are adding PDF and Print layouts, sorry this not so simply as we thought

BUT there yet very many what need add...

Regards
Andrew

Great thanks again Andrew, and for your time!
All noted.
Also :
- is it possible to install the CCK + the components (real estate, car manager...) on a same site?
- about Amazon like market-place and development I would like to ask you questions : is possible, but by mail or private for confidentiality?
Best regards,
Henri

Yes you may to one site install OS CCK and other our components

And in CCK - you may at one time manage as example any Entities: houses and vehicles, cooks and cakes....
And for every Entity you will have self add and show layouts and self fields

Yes, you may write to us with help Contact us form. But at common questions we prefer reply by forum, by email we reply only to Pro members

Regards
Andrew