Request and register a shipping quote
From the draft order screen an admin needs to be able to request a quote for the current draftorder. They can do this using Todays or Manual. When they choose Todays, Todays will get an email with the draft order details (line items) and todays should get a link where they can submit the quote amount which will be saved with a timestamp. The admin gets a notification and can copy the amount to the draft order's shipping cost.
When choosing manual, we assume the admin already requested a quote with a provider and just wants to register it here, as in 'We got this quote on this datetime from this provider. SO the admin need to fill out a provider name, amount and timestamp to register it.
Next to this, a markup percentage. This should be a fixed stored value (10% for example) and should be added between the quote amount and the entered shipping costs on the draft order.