Hi Lena29 and everyone,
What did you translate in the end? My wife is going to apply for a Family permit in Spain too. I'm happy to translate the wedding certificate but everything else will take ages (flat contract, work contract, empadronamiento, vida laboral, payslips, utility bills). At least reading here it seems many people can certify a translation. I can translate it and a friend (translator) can sign that it's a ‘true and accurate translation of the original document’.
https://www.gov.uk/certifying-a-document
But it will take me a while to translate all the contracts and documents and I don't even know if they need it.
Cheers, T