No anúncio, dizia que ainda há uma vaga de garagem disponível.

No is a contraction of em + o:

• em = in, on, at
• o = the

So:

• em o anúncio → no anúncio

In Portuguese, these contractions are very common and usually required:

• em + o = no
• em + a = na
• em + os = nos
• em + as = nas

So No anúncio literally means in the advertisement or in the ad.

The comma separates the introductory phrase No anúncio from the rest of the sentence.

It works a bit like English:

• In the ad, it said...

This kind of comma is common when a time/place/context phrase is moved to the front for emphasis or clarity.

Without the comma, No anúncio dizia... may still be understood, but the comma makes the sentence feel more natural and organized in writing.

Dizia is the imperfect form of dizer (to say).

Here it means something like:

• it said
• it was saying
• the ad said

The imperfect is often used in Portuguese to report what something stated or what was written, especially when the focus is not on a single completed event but on the content or background information.

So No anúncio, dizia que... is a natural way to say:

• In the ad, it said that...

In English, we often just use the simple past (said), but Portuguese may use the imperfect here more naturally.

The subject is not stated explicitly, but it is understood from context.

In this sentence, dizia refers to the content of the ad, so the idea is:

• the ad said
• it said in the ad

Portuguese often leaves the subject unstated when it is obvious from the context.

So even though there is no written o anúncio dizia, that is basically the understood meaning.

Que here means that and introduces a subordinate clause.

So:

• dizia que ainda há...
• it said that there is still...

Just like in English, say/tell + that is very common.

Examples:

• Ela disse que vinha. = She said that she was coming.
• O texto dizia que... = The text said that...

In Portuguese, que is very common in this structure and normally should be included here.

Há is from the verb haver, and in this kind of sentence it means there is or there are.

So:

• há uma vaga = there is one parking space

This use of haver is very common in formal or written Portuguese.

You could also hear:

• tem uma vaga in everyday spoken Brazilian Portuguese
• existe uma vaga in a more literal there exists sense

But in an ad or more standard written style, há sounds very natural.

Important point: this há is impersonal, so it stays singular even if the noun after it is plural:

• Há uma vaga. = There is one spot.
• Há duas vagas. = There are two spots.

Not hão duas vagas.

This is a very good question.

The sentence reports what the ad said, but the content of that statement is presented as still true at the relevant moment:

• No anúncio, dizia que ainda há uma vaga...
• In the ad, it said that there is still one space available.

Using há in the present suggests the availability is current or being presented as current.

This is similar to English, where you can say:

• The ad said there is still one spot available.

instead of

• The ad said there was still one spot available.

Both ideas can exist depending on the context, but the present here helps keep the information vivid and current.

Ainda here means still.

So:

• ainda há uma vaga = there is still one spot

It suggests that the parking space has not been taken yet.

Depending on context, ainda can also mean things like:

• yet
• even
• still

But in this sentence, still is the best match.

Uma vaga de garagem means a parking space or a garage parking spot.

Breakdown:

• uma = a / one
• vaga = vacancy, opening, spot, space
• de garagem = of garage / for a garage

In Brazilian Portuguese, vaga is commonly used for a parking space, especially in apartment buildings, offices, and property ads.

So this is not talking about a whole garage. It means one place where a car can be parked.

Portuguese often uses noun + de + noun where English might use a noun as an adjective.

So:

• vaga de garagem = parking space / garage space
• literally: space of garage

This structure is extremely common in Portuguese.

Other examples:

• porta de vidro = glass door
• sala de aula = classroom
• cartão de crédito = credit card

So vaga de garagem is just the normal Portuguese way to express this idea.

Because disponível has the same form for masculine and feminine singular.

So you get:

• um lugar disponível
• uma vaga disponível

The adjective does agree in number:

• uma vaga disponível
• duas vagas disponíveis

But in the singular, masculine and feminine are both disponível.

Yes, both are possible, but they sound a little different in tone and style.

• há uma vaga de garagem disponível
  More standard, common in writing and formal contexts

• tem uma vaga de garagem disponível
  Very common in spoken Brazilian Portuguese, more conversational

• existe uma vaga de garagem disponível
  Grammatically fine, but often sounds a bit more literal or formal, depending on context

In an advertisement, há is a very natural choice.

Yes. That is a very clear and direct version.

Compare:

• No anúncio, dizia que...
• O anúncio dizia que...

The second one states the subject explicitly: the ad said.

The original version is slightly less direct and more impersonal, which is common in Portuguese. Both are correct, but the original sounds very natural in context.