issue with access to products in 1.7

[cuccaro]

i need to show some of my products only to certain users, but by default prestashop 1.7 shows to the user (that can't see that category) the message "You haven't got access to this category", which i don't like very much. I've been looking for some addons, but no one does the work i need, that's to say just disabling the view of the product for those customers who can't see it. Most of them show the message "You can't buy this product", and i don't really like it.

An alternative could be showing the button "ask for a quotation" to those customers who can't see the price of the product, 

Is it possibile to display the button "ask for a quotation", thus disabling the button add to cart, only on selected products (coming from different categories)?
I'm imagining some module that adds a tab to my product page, where i check the possibility to show the ask for a quotation or the selected group of customers.

Any idea? i'm i asking something impossible? Thank you for your help.

[cuccaro]

EDIT: Maybe i can be a little bit clear about my request.

I'm looking for a way that allows to modify the visibility of the price for certain products (that can belong to different categories) AND according to different user categories.
For example: i want to be able to hide the price for the product PEN that belongs to the category OBJECTS for my user category CUSTOMER, while my other user categories PARTNER and AGENTS are able to see that price. But i also want that the user category CUSTOMER is able to see the price for the product PENCIL, which belongs as well to the category OBJECTS.
 

Can somebody help me? Thank you.

 

Edited March 22, 2018 by cuccaro (see edit history)