Landed Costs are a great fit for incorporating fixed costs into the cost of finished goods. 

Support for Landed Costs added to Manufacturing Orders is new feature of the Version 14.0 release. 

Setup:1.

2. Create a Service Product Category with the Stock Input Account set to the default Expense account you would like to use.

3. Create a Service Product that belongs to that category and check Is a Landed Cost on the Purchasing tab:

OPTIONAL:

Create a smart button and a customized search view for faster landed cost creation and access:

<div class="oe_button_box" position="inside">
  <button name="463" type="action" string="Landed Costs"
          icon="fa-plus-square" groups="stock.group_stock_manager" 
          attrs="{'invisible': [('state', '!=', 'done')]}"
          context="{'search_default_mrp_production_ids': name,
                    'default_target_model': 'manufacturing',
                    'default_mrp_production_ids': [active_id]}">
    
  </button>
</div>

Note: 463 is the ID of the Window Action you see in the URL when you navigate to Inventory -->  Operations --> Landed Costs

<field name="picking_ids" position="after">
  <field name="mrp_production_ids"/>
</field>

Scenario:

Product Component is purchased at $10 per unit.

A Bill of Materials shows that three units of Component are required to make one Widget.

The Cost Analysis of a Manufacturing Order producing two units shows the pre-landed cost of $30 per unit:

If you added the optional customization, the landed cost is created via the smart button:

If not, you would use the Inventory --> Operations --> Landed Costs Menu.

Adjust the account, split method and/or cost as needed.

This example will add $6 to the cost of a unit of Widget (because two were produced).

The Journal Items for the landed cost are:

You can see the expense account is being credited (reduced) so you either need to already have the expense of the overhead booked, or book it soon after to have sensible financial reports

The Inventory Report (and the Product Master) will now reflect the updated product cost:

If you SELL any of the finished goods before you process the landed cost, Odoo will create journal items that reflect the additional amount of inventory and cogs that need to be booked.  A credit will remove overheard for every unit already sold and a debit will add overhead to cost of goods. The stock interim delivered account is used as a clearing account for these amounts.

Landed Costs can be used to add a variety of overhead costs to finished Goods.  Examples are leases of equipment, maintenance, supervisory salaries, utilities, facility rent, etc.

This example added a single landed cost to a single manufacturing order, but you can apply multiple costs to multiple completed manufacturing orders (say at the end of the month) if needed.

You can also record a Landed Cost directly from a Vendor Bill.  For more information, see the Integrate Landed Costs lesson from the Inventory Course on our eLearning platform at https://www.odoo.com/slides/slide/integrate-landed-costs-662