Les charges de copropriété coûtent cher.

Because les charges de copropriété refers to the various building or condo fees taken together as a category. In French, these fees are normally spoken of in the plural: les charges.

So French treats it a bit like the service charges / the maintenance fees rather than a single abstract cost.

Because the subject is plural: Les charges.

In French, the verb agrees with the subject:

• La charge coûte cher = The fee costs a lot / is expensive
• Les charges coûtent cher = The fees cost a lot / are expensive

So coûtent is the ils/elles form of coûter in the present tense.

Here, cher is used adverbially in the expression coûter cher, which means to cost a lot / to be expensive.

In this expression, cher usually stays unchanged:

• Ça coûte cher
• Les réparations coûtent cher
• Les charges coûtent cher

So even though charges is feminine plural, cher does not agree here.

Yes. That is also correct.

There is a small nuance:

• Les charges de copropriété coûtent cher emphasizes the amount of money they cost
• Les charges de copropriété sont chères simply describes them as expensive

In everyday use, both are natural.

Note that with être, the adjective agrees:

• Les charges sont chères

In this context, charges means fees, service charges, building expenses, or shared ownership costs.

It does not mean charges in the sense of accusations, electrical charges, or attacks.

In property language, les charges is a very common word for ongoing costs connected with a home or apartment.

Copropriété refers to a property ownership system where a building is divided among different owners who each own their own unit and share responsibility for common areas.

In practice, it often corresponds to:

• condominium ownership
• shared ownership of an apartment building
• the condo association / homeowners’ building arrangement

So charges de copropriété are the fees linked to that shared arrangement.

Because de + noun is often used in French to specify the type or category of something.

Here, charges de copropriété means something like:

• condominium fees
• co-ownership fees
• fees connected with shared ownership

This is similar to patterns like:

• une carte de crédit = a credit card
• des frais de transport = transport costs
• des charges de copropriété = condo/shared-ownership fees

Using de la copropriété would usually sound more specific and less like the standard set expression.

Les is the definite article, meaning the.

French often uses the definite article where English might use:

• the
• no article at all
• or a more general expression

So Les charges de copropriété coûtent cher can mean:

• The condo fees are expensive
• Condo fees are expensive

French commonly uses les to talk about things in a general sense.

Coûtent is pronounced basically like coûte.

Important point: the -ent ending of third-person plural verbs in the present tense is usually silent.

So:

• il coûte
• ils coûtent

These are pronounced the same.

A rough pronunciation guide:

• coûtent ≈ koot

And the whole phrase:

• coûtent cher ≈ koot shair (roughly)

Yes, very much so.

Coûter cher is a very common French expression meaning:

• to cost a lot
• to be expensive

You will hear it in many contexts:

• Cette voiture coûte cher.
• La vie à Paris coûte cher.
• Les réparations coûtent cher.

So this sentence uses a very standard French pattern.

Usually, people say les charges de copropriété in the plural, because these fees are normally thought of as a set of recurring costs.

You might see singular une charge, but that usually refers to:

• one specific fee
• one expense item
• one burden/cost

For the general idea of condo fees, the plural is much more natural.

It is a prepositional phrase that modifies charges and tells you what kind of charges they are.

So:

• charges = fees / costs
• de copropriété = related to co-ownership / condominium management

Together, they form one noun phrase:

• les charges de copropriété

It can be either, depending on context.

Without context, French often allows a general reading:

• Condo fees are expensive

But in a conversation about a particular apartment or building, it could also mean:

• The condo fees are expensive

So the sentence itself is neutral; context tells you whether it is general or specific.