The appointment is the credential
Some countries accept a translator who states their own competence. Serbia is not one of them. The signature has to come from a court-appointed translator, a sudski tumač, and that appointment is a matter of public record rather than a claim made on the page. A clerk can look it up, which is precisely why it is asked for.
Bound, stamped, and hard to tamper with
The Serbian text does not travel alone. It is fastened to a copy of the source page and stamped across the join, so the two cannot be separated and re-paired without leaving a mark. This is why the returned set feels more like a small booklet than a printout, and why it should reach the reading office in one piece, still fastened.
Serbian, and the words that must not drift
Serbian is the language the file has to be in, and the terms inside it matter more than style. Names of courts, ranks, and legal statuses are rendered consistently across the whole set, because a reader comparing two documents will treat two different renderings as two different things. Consistency across pages is worth more here than an elegant sentence.
What it costs and how long it sits
The rate is £25 for each side of paper as issued, so a double-sided extract counts twice and a stapled schedule counts page by page. Standard turnaround is 2–4 business days from a legible scan; express work lands in 24–48 hours. Cost is set by the paper you send, so trimming the bundle to the pages actually being filed is the honest way to spend less.