The one charge that is actually published
Only the stamping fee has a printed price. It is £45 for each paper handled by post, and £40 for each paper on the next-day route that registered businesses may use. That figure does not move with the destination, the paper type or how urgent the matter is. Every other line on a quote you receive belongs to somebody else, and knowing that makes a quote much easier to read.
The cost before the cost
A paper can only be stamped if a signature on it matches a sample the office holds. That usually means buying a signed version first. Edinburgh Registration Service prints certified extracts of births, marriages and deaths, each one a signed record rather than a copy. A fresh extract can travel while the one at home stays with you, and paying for that peace of mind is generally cheaper than replacing a lost record.
Why there is no second bill
Italy has been inside the Hague Apostille Convention since 1978. That single fact removes the consular half of the old route and, with it, a second fee, a second queue and a second journey. An apostille from United Kingdom to Italy is finished when the slip is attached in Milton Keynes. Nothing further is collected in Britain, and nothing has to be gathered in Rome before the paper is sent.
Language, and where it sits in the budget
Italian offices work in Italian, so a rendering of the paper is a common extra even though no British rule asks for one. Price it after the stamp, not before, because the translator should be able to carry the slip across as well as the paper. Translators charge by length or by page, so a short extract is cheap and a long court bundle is not, and that difference dwarfs the stamping fee on big jobs.
Where the money actually leaks
The expensive mistakes are all repeats. Stamping a paper the Italian reader never wanted, stamping the wrong version and having to start again, or sending a bundle untracked and paying for replacements. Deciding early which body in Italy will read the page removes most of that risk for nothing. An Edinburgh apostille for Italy is a small fixed charge wrapped in decisions that are worth much more.