Hello,
I am a native spanish speaker and have experience in translation between English and Spanish.
I would like to add that I also have a long experience in research in the education and labor sector. For this reason, I am very familiar with the business categories, specifically with the Spanish codes: CNAE (National Code of Business Activities). I believe that being familiar with this code is fundamental to do a good translation, in this case.
I will carry out the translation considering the headings used in the CNAE.
Regarding the translation that you request as example, the literal translation would be "Reparaciones de fontanería". However, if it is a main business category, it would be translated as "Instalaciones de fontanería". If it is a sub-category within a main category "Plumbing Installations", i would translate as "Reparaciones y mantenimiento de fontanería" if there is not an independent sub-category called "Plumbing Maintenance" in the list.
Looking forward to hearing from you.
Regards,
Vanessa