How to add required steps to checkout

[markbeazley]

I'm new to PrestaShop development, and would like some guidance on what the best way to add some additional steps to the checkout system using a module. 

 

For the site I am currently working on some customers will need to tick 2 separate checkboxes (these need to be ticked for the order to continue so will need PHP verifications as well as JS in the template), and another set of customers (based on shipping address) will need to pick an option from a select drop down (populated by a javascript ajax call) before placing there order (validation will again be needed on the PHP side for this) these orders will then need some checks run on them by a third party service I am integrating with, while the orders are waiting for these checks to be done they will need to be set to a special order status.

 

From reading the forum what little I've found on the subject (and most information seems to be quite a few years old) I may need to override the order class to do this, but the documentation seems to suggest I shouldn't be using overrides any more. I think I will need to add a new table to store the check results with a link back to the order id.

[tuk66]

Look at this module:

 

Custom Checkout and Customer and Address Fields manager Module
http://addons.prestashop.com/en/19736-custom-checkout-and-customer-and-address-fields-manager.html

[markbeazley]

Had a look at it but as its a paid module I'm guessing its source is closed, which doesn't really help identify which hooks I should be using to achieve the same thing. Whilst the module itself may work for the two checkboxes I need to add, it doesn't work with the third party system I need to integrate with to populate the drop down based on a postcode lookup. The validation fort he drop down  only has to be required for some countries, which it seems the module can't do.