Contratamos el servicio de catering y revisamos la insonorización.

They are most likely preterite here: we hired / we checked.

However, there is an important detail: for -ar verbs, the 1st person plural form (nosotros) is the same in the present and the preterite.

So:

• contratamos can mean we hire or we hired
• revisamos can mean we check/review or we checked/reviewed

You need context to know which one is intended. In a sentence about completed event preparations, the past meaning is usually the natural one.

Because Spanish often omits subject pronouns when the verb ending already shows who the subject is.

Here, contratamos and revisamos already tell you the subject is we.

So:

• Contratamos... = We hired...
• Nosotros contratamos... = also We hired..., but with extra emphasis or contrast

Spanish prefers the shorter version unless the speaker wants to stress we specifically.

Both are possible.

• Contratamos el catering = more direct and very natural
• Contratamos el servicio de catering = a bit more explicit, formal, or business-like

Adding servicio makes it sound like you are talking about the service as something contracted or arranged, not just naming the general idea of catering.

Yes. In Spain, catering is very common, especially in events, weddings, conferences, and business contexts.

It is a borrowing from English, but it is well established in everyday Spanish in Spain. You will often hear:

• el catering
• un servicio de catering
• la empresa de catering

A more purely Spanish alternative might be something like servicio de comidas, but catering is usually the more natural choice in this context.

Because de catering is describing the type of service.

In el servicio de catering, the structure is:

• servicio = the main noun
• de catering = a complement telling you what kind of service it is

This is similar to:

• servicio de limpieza
• clase de español
• gafas de sol

Using del catering would usually suggest something more specific, like of the catering, and that is not what is meant here.

Not in this sentence.

A very common learner mistake is to connect Spanish revisar directly with English revise. In many cases, revisar means:

• to check
• to inspect
• to look over

So here, revisamos la insonorización means something like we checked the soundproofing.

If you mean revise in the sense of studying again for an exam, Spanish often uses repasar. If you mean improving a text, corregir or sometimes revisar may be used depending on context.

Insonorización is a feminine noun, so it takes la.

A very useful pattern is that nouns ending in -ción are usually feminine:

• la organización
• la información
• la construcción
• la insonorización

So once you see -ción, feminine is a very good guess.

It means soundproofing or sound insulation.

It refers to making a room, building, or space better at blocking or reducing sound. In this sentence, it likely means they checked the venue’s soundproofing.

A close alternative is aislamiento acústico, which is also common. Very roughly:

• insonorización = soundproofing
• aislamiento acústico = acoustic insulation

In many real situations, they overlap a lot.