Conditional display of product customization block

[Kulik Design]

Hi all,  I've run into a situation.  I have products that may or may not have customization (personalization) and said customization includes an up charge. I want to include/not include the Customization section based on the customer choice. My thought was combo product with custom/no custom attribute with appropriate up-charge on custom.  Then with a hook on the product page check $params do the logic and set is_customizable to either true or false.  My assumption is the cart will handle the rest as far as showing or hiding the customization section, validation (is required) and storing the values.  Using this code:   $params["product"]->product["is_customizable"] = false;

However when I try to set that value I get an error "Indirect modification of overloaded property".    My question, I may be down a rabbit hole here; How would it be best to go about this?  I hope to keep the solution contained in a custom module I wrote. 

Edit: I'm working in ver 8

Edited May 17 by Kulik Design
add prestashop version (see edit history)