2016 Audi A3 - Android Auto

I'm the owner of a new (to me) 2016 A3 and would like to get android auto installed. How big of a job is it and does anyone know how much it roughly costs? I'm in the UK

I've seen online they may have to retro fit and full new infotainment unit, which I would just leave but then seen options on SSD. I likely wouldn't do it myself and would go to a specialist but just curious to see whether it's worth it or not.

Thanks