“Caretaker” has a number of uses. It is a noun.

Schools and apartment blocks normally have caretakers (porteros, vigilantes, conserjes). A similar word is “janitor” (conserje). Often a caretaker is responsible for cleaning and repairs.

There are other options too: as compound (compuesto) nouns.

– There are “caretaker governments” (gobiernos de transición), and sometimes sports clubs have “caretaker managers”.

– Italy and Belgium have had many caretaker governments, because there was no obvious winner in the elections, and the politicians cannot agree to work together.