Where Somalia stands
Somalia has not joined the Hague Apostille Convention, so a British certificate on its own does not answer for a paper used there. The route that applies runs through certification by the FCDO Legalisation Office and then a consular stamp, in that order. Two desks, and neither of them is a place you visit. The whole job is done through envelopes and the addresses written on them.
What a postal route changes
When there is no counter, nobody looks at your papers while you stand there and tells you the name is spelled two ways. Errors surface days later, in an envelope, and each one costs another cycle through the post. That is the real difference between this route and an errand you can run on a Tuesday afternoon in the city centre.
What is actually in your hands
The first decision is which version of the record goes. Coventry Register Office holds the registers for births, marriages and deaths, and a fresh certified copy drawn from one of them is made to be sent away, which your own certificate never was. Choosing that copy takes one trip and removes the worst thing that can happen on a long postal route.
The second is where the paper lands when it returns. Somebody has to be at that address, over several weeks, able to receive a package and pass it on to the next stage. The third is how many records go together, since each one is handled and charged in its own right rather than as part of a bundle.
Paying at a distance
The British stage has a printed price: £45 / document by post, or £40 / document on the next-day line that registered businesses use. That figure is paid before anyone in Somalia has seen the paper. The consular charge comes later, is set by that desk rather than this one, and no reliable figure for it can be given from here.