Podstanarka pita hoće li joj kaucija biti vraćena ako se iseli prije jeseni.

Podstanarka means a female tenant / lodger / subtenant. It is grammatically feminine because the noun ends in -a, which is a very common feminine ending in Croatian.

The masculine equivalent would be podstanar.

So:

• podstanarka = female tenant
• podstanar = male tenant

In this sentence, the feminine form matters because later words also match that situation, such as iseli se referring to she moves out.

Pita is the 3rd person singular present tense of pitati = to ask.

So:

• ja pitam = I ask
• ti pitaš = you ask
• on/ona pita = he/she asks

Here, podstanarka pita simply means the tenant asks.

You could also see upitati in Croatian, but pitati is the normal everyday verb for to ask.
Je pita would mean something different, because je is an auxiliary or a short pronoun in other contexts; it is not needed here.

Hoće li is a very common way to introduce an indirect yes/no question or a future-related clause.

Here it means something like:

• whether ... will
• if ... will

So pita hoće li joj kaucija biti vraćena means: she asks whether her deposit will be returned to her

Grammatically:

• hoće = will
• li = a question particle

Together they often appear in questions:

• Hoće li doći? = Will he/she come?

And after verbs like pitati, they introduce an embedded question:

• Pita hoće li doći. = She asks whether he/she will come.

In standard Croatian, the particle li normally comes after the first stressed word, and in this structure that word is hoće.

So:

• Hoće li... = correct
• Li hoće... = not correct

This word order is fixed in standard usage.

Joj is the dative singular form of the pronoun ona = she / her.

In this sentence, it means to her.

So:

• joj kaucija biti vraćena = the deposit be returned to her

It does not mean possession here in the same way English her can. Croatian uses the dative pronoun because the verb phrase naturally takes the person receiving the returned object as an indirect object.

Compare:

• Vratili su joj novac. = They returned the money to her.

Because kaucija is the grammatical subject of the passive construction.

The phrase kaucija biti vraćena literally means:

• the deposit to be returned

In Croatian passive structures, the thing being acted on becomes the subject, so it appears in the nominative:

• Kaucija će biti vraćena. = The deposit will be returned.

That is why it is kaucija, not kauciju.

Croatian commonly forms the passive with:

• biti = to be
• plus a passive participle

Here:

• biti = to be
• vraćena = returned (feminine singular passive participle)

So:

• kaucija biti vraćena = the deposit be returned

This works much like English will be returned.

The participle agrees with kaucija, which is feminine singular, so we get:

• masculine: vraćen
• feminine: vraćena
• neuter: vraćeno

Because vraćena must agree with kaucija, and kaucija is a feminine singular noun.

Agreement in Croatian is very important. The passive participle changes form depending on the noun it refers to.

Examples:

• novac je vraćen = the money was returned
  (novac is masculine)
• kaucija je vraćena = the deposit was returned
  (kaucija is feminine)
• pismo je vraćeno = the letter was returned
  (pismo is neuter)

This is about aspect.

The verb iseliti se is perfective, and iseljava se would be the imperfective form from iseljavati se.

In Croatian, after ako when talking about a future completed event, Croatian often uses the present tense of a perfective verb:

• ako se iseli = if she moves out / if she does move out

This sounds natural because the meaning is about one completed action in the future.

By contrast, an imperfective form such as iseljava se would suggest an ongoing or repeated process, which does not fit as well here.

Iseliti se / iseliti means to move out.

The se is part of the verb in this usage. Many Croatian verbs are reflexive or are commonly used with se.

So:

• iseliti se = to move out
• seliti se = to move house / be moving
• useliti se = to move in

In this sentence:

• ako se iseli = if she moves out

The preposition prije requires the genitive case.

So:

• prije + genitive = before

The noun jesen changes to jeseni in the genitive singular:

• nominative: jesen = autumn
• genitive: jeseni = of autumn / before autumn

That is why the sentence says:

• prije jeseni = before autumn

Other examples:

• prije škole = before school
• prije ručka = before lunch

No, not in this sentence.

Because the preposition prije clearly means before, prije jeseni can only mean before autumn.

If you wanted to say in autumn, Croatian would use a different structure, for example:

• u jesen = in autumn

So:

• prije jeseni = before autumn
• u jesen = in autumn

Croatian word order is more flexible than English, but there are still rules, especially for clitics like li and joj.

In this sentence:

• hoće comes first
• li comes right after it
• joj is also a short unstressed word, so it appears early in the clause

That gives:

• hoće li joj kaucija biti vraćena

A more English-like order such as hoće li kaucija biti vraćena joj would sound unnatural.

So the sentence follows normal Croatian clitic placement:

• first stressed element
• then short unstressed elements like li, joj
• then the rest

Yes, you may hear or read da li in some contexts, especially in speech or in some regional styles:

• pita da li će joj kaucija biti vraćena

But hoće li is very natural and standard here, and many teachers prefer learners to get comfortable with it early.

So both may occur, but:

• hoće li is very common and stylistically solid
• da li also exists, but some speakers and style guides prefer to avoid it in more formal standard usage

Yes, kaucija is a common and standard word for a security deposit, especially in renting contexts.

So if you are talking about money left as a guarantee when renting an apartment, kaucija is exactly the right word.

You may also see it in legal or business contexts with the same basic meaning.