UK passport office does a fine job scamming without needing external companies
UK passport renewal Sir? That'll be 72 quid from the UK.
Oh, I see you are applying from outside the UK? We'll you still have to send the application to the same address in the UK and use the same form, but we are going to charge you 148 quid instead.
Was so annoyed I even called them to find out why the price was double. "More administration" was the vague but predictible response I received.