Apostille vs. Embassy legalisation for Russia
People often assume that a degree and a birth certificate must be handled by different systems, because they were issued by bodies that have nothing to do with each other. On this corridor that assumption is wrong in a helpful way. An apostille for Russia is one certificate applied to British public documents generally, so the sorting you expected to do does not exist.
The comparison with a consular corridor makes the point. There, a receiving state may look at each kind of paper on its own terms and route it accordingly. Here an apostille issued in Wolverhampton for use in Russia is the same object whatever it is attached to, which is why a mixed pile can be dealt with in one go.
Russia's Hague status and what it means
Russia has been inside the Hague Apostille Convention since 1992, and the United Kingdom is inside it too. Shared membership is what allows one office to speak for the whole route, and it is also what makes the route indifferent to document type. The treaty is about how states recognise each other's paperwork, not about what any individual sheet contains.
The Wolverhampton to Russia route step by step
The variable stage is the first one. Births, marriages and deaths registered locally are served by Wolverhampton Register Office at the Civic Centre, St Peter's Square, WV1 1RU. Degrees come from the university that awarded them, company records from the registry that keeps them, and court papers from the court office that issued them, each with its own way of sealing a copy.
The fixed stage follows. Everything goes by post to the FCDO Legalisation Office at PO Box 6255, Milton Keynes MK10 1XX, which handles British apostilles for the whole country and deals with people through the post rather than across a counter. Papers come back to the sender, certificate attached, ready to travel on.
Cost and timing for this route
The charge is £45 per document by standard post, or £40 per document on the next-day service that registered businesses may use. Because it is charged per sheet, three documents are three fees no matter how neatly they fit in one envelope. Gathering the papers usually takes longer than certifying them, so start with the slowest issuing body.
Sending a mixed batch
If several papers are going to Russia together, list them by issuing body rather than by importance, and chase the slowest one first. Anyone reading about document legalisation for Russia will find the same single-certificate answer for each item on that list. Keep the returned documents whole, and resist the urge to re-staple a bundle into a tidier shape.