The job starts with your answers
Armenia wants papers in Armenian, so anything you file there has to be translated before it can be read. That part is fixed. What is not fixed is how quickly it happens, and that turns on you: the images, the spellings and the deadline. A translator holding all three can begin the same day, while one waiting on a name cannot begin at all.
The three things worth getting right
Send colour images rather than grey photocopies, because a seal that has faded in the scan has to be described as faint. Give every name as your passport prints it, including middle names you never use. Then name the day the paper is due, since the express route is worth paying for only when the deadline is genuinely tight.
Who signs, and what the signature says
An ITI or CIOL qualified certified translator does the work and then signs a dated statement that the Armenian matches the English page put in front of them. That statement carries a name, so a reader with a query has someone to put it to. It says nothing about whether your original is genuine, and it was never meant to.
What it costs and where the source sheet comes from
At £25 for each side as issued, the price falls out of the page count alone, and a half-empty sheet costs what a dense one costs. Standard work runs 2–3 business days and express 24 hours, each counted from the arrival of readable images rather than from your first email. Where the paper is a birth, marriage or death record, Bristol Register Office at The Old Council House, Corn Street, Bristol BS1 1JG issues fresh certified copies, so your own original stays in your drawer.