Using a prepositional phrase with the verb acabar

Question

The following sentence came up on Glossika:

A nuestro vecino le acaban de instalar aire acondicionado en su casa.

I understand the gist of the sentence but I've never seen the verb 'acabar' used in the same way as 'gustar'.

Three related questions:

1. Is this construct used for the verb 'acabar'?

2. If so, then how is it any different from:

Nuestro vecino acaba de instalar aire acondicionado en su casa.

3. Am I correct in thinking that it should be instead:

A nuestro vecino le acaba de instalar aire acondicionado en su casa.

Answer 1

It is not exactly the same structure as "gustar". The "le" in your sentence is a dative of interest. The verb "acaban" is in third person plural because the subject is an unspecified third person, as explained here. The translation of the sentence

A nuestro vecino le acaban de instalar aire acondicionado en su casa

would be

• They have just installed air conditioning in our neighbor's house

or more naturally

• Our neighbor has just had air conditioning installed in his house.

The indirect object pronoun le means roughly for him, as in "they installed the air conditioning for him". The third person plural "acaban" is because the subject is unspecified and irrelevant. For such unspecified subjects, the plural is used, even if the subject may actually be a single person. A similar example is

• Le han cortado el pelo muy mal (They have given him a very bad haircut)

where the hairdresser is probably a single person, but still the third person plural han cortado is used.

The sentence you suggest in 2.

Nuestro vecino acaba de instalar aire acondicionado en su casa

has a different meaning, because it implies that the neighbor has installed the air conditioning himself.

Additional note: the title of your question mentions a "prepositional phrase", though the body seems to ask about something else. To clear any doubts, "acabar de + verb" (see meaning 11) is a standard verb phrase that refers to an action that has just been completed. The translation could be "have just + verb".

Answer 2

Although in the verbal phrase “acabar de instalar” the main verb is acabar, the actual core of the phrase is instalar, and all the verbal arguments (subject, direct object, indirect object, etc.) that appear in the rest of the sentence refer to instalar. This is just as when you use querer + infinitive, for example. This looks like a minor point but is significant because otherwise you'd be tempted to think that the IO pronoun le in this example has something to do with acabar. The “normal” position of the IOP here would be “acaban de instalarle”, but the pronoun has been “raised” (analogous to the process that gives you “le quiero decir” from “quiero decirle”). This doesn't change the meaning at all; the pronoun is still the indirect object of the inner verb (the infinitive).

So what needs to be analyzed is instalarle. The IOP can be analyzed as such or as a dative of interest, like @wimi says. In any case it means the action of the verb (to install an A/C) is being done for the benefit of the IO (our neighbor). In English, this kind of meaning is conveyed by a periphrasis with passive voice: “Our neighbor has had an A/C installed in his house”, or else by a generic third person active voice: “They have installed an A/C in our neighbor's house” or some other similar rephrasing. This is because English uses indirect objects for a much more restricted set of meanings, mostly with verbs of giving, sending or communication (“They have given our neighbor a gift”, “She has written our neighbor a letter”).