Well, as a matter of fact, Norma just recently created a post here, outlining how to utilize multiple price lists in a single Quotation. I would be wondering if this approach could not get adopted to your needs: https://www.odoo.com/forum/1/278106 (leave your Kudos there, I'm but the mail man)

Hi,

Option 1: python code

from odoo import models, fields, api

class SaleOrderLine(models.Model):

    _inherit = 'sale.order.line'

    @api.onchange('product_id', 'product_uom_qty', 'order_id.pricelist_id')

    def _onchange_product_id(self):

        super()._onchange_product_id()

        if self.product_id and self.product_id.lst_price == 0:

            # If sales price = 0, use pricelist

            price = self.order_id.pricelist_id.get_product_price(self.product_id, self.product_uom_qty, self.order_id.partner_id)

            self.price_unit = price

        else:

            # Otherwise, keep product’s sale price

            self.price_unit = self.product_id.lst_price

When you add a product to a quotation/order, Odoo checks:If product.lst_price == 0, it gets the price from the pricelist. Otherwise, it uses the product’s normal sale price.

Option 2: Automated action

If you want a no-code approach (in Odoo Studio or base system):

Go to Settings → Technical → Automation → Automated Actions

Create new:

Model: Sale Order Line

Trigger: On Creation & Update

Condition: record.product_id.lst_price == 0

Action:Execute code

record.price_unit = record.order_id.pricelist_id.get_product_price(

    record.product_id,

    record.product_uom_qty,

    record.order_id.partner_id

)

This lets Odoo auto-fill the price only if product price = 0.

Hope it helps

The correct way to do this in Odoo17 is simply this (in sale order line model)

	​
def _get_pricelist_price(self):
    """Compute the price given by the pricelist for the given line information.

    :return: the product sales price in the order currency (without taxes)
    :rtype: float
    """
    self.ensure_one()
    self.product_id.ensure_one()

    if self.product_id.lst_price is False or self.product_id.lst_price == 0:
        return super()._get_pricelist_price()
    else:
        return self.product_id.lst_price