No Electrician Needed
Everything you can install yourself — all the solar, and the whole 12V range.
12V is extra-low voltage: the buried cable is safe to cut, the fittings are safe to handle, and you can lay, move, extend and re-aim the entire system without touching mains wiring. That is the reason it is the domestic garden standard.
The one exception is the supply feeding the transformer. If you already have a suitable outdoor socket, plug it in and you are done. If you need a new outdoor socket or circuit, that is a new circuit — notifiable under Part P in England and Wales — and it needs a qualified electrician. One hour of their time, once.
Solar needs none of that at all.
