An electrician did the inspection and issued a boletin for my neighbours and he charged 200 euro.
However, as you don't put where you are in Spain on your profile, might be a bit silly me recommending an electrician in, say, Madrid if you live in, say, Marbella.
However, what tariff were you on before? All of us here who have had smart meters fitted stayed on the original tariff. In my case, 5.75Kw which is fine.