Use form in the content type who use a form in a node?
for example
I want to create a content type that show in this, my product , description , ....
and bottom on this node have a form to get comment and price recommended of user.

I test Webform but not in use for me!

who to create this content type?
It depends on what exactly you want to do. Maybe you just make one contenttype for your product and let users comment this product with nodecomments. This way you can make an extra contentype for your comments with extra fields (e.g. price.). There is no need in displaying these comments afterwards. But why does the webform-module not work for you?