You're asking about how to set up an Inventory Valuation report to display purchase and sales details. It's a bit tricky if you want to match Odoo's existing report structure exactly, but here's how you can start. Instead of creating a brand new modle, you can work with Odoo's existing framework.

First off, check out the `Report` and `Wizard` functionalities in Odoo. For those radio buttons and submit screens, a Wizard is your friend. Wizards act like temporary models, guiding the user through actions, making them ideal for grabbing radio button selections.

You'll want to create a Wizard modle with fields for your inputs. Then, set up a button in a form view that triggers a Python function when clicked. This function should pull data from source models like `purchase.order` or `sale.order`, and restructure it for your report.

The collapsing/expanding data behavior is managed through tree and form views, or maybe even JavaScript if you're into that. For making reports, QWeb is good for flexible HTML/PDF outputs that can mirror existing report styles.

Yeah, Odoo can be a bit weird with its logic. This stuff can get complex, so keep in mind testing is a must. Adjust your dev environment first, and think about user-friendliness since the end-users will navigate these screens.