Slegs indien die bouplan gereed is, betaal ons die aansoekfooi.

Slegs means only, and indien means if.

Together, slegs indien means only if. It introduces a condition and emphasizes that the action happens in that condition alone.

So the sentence structure is:

• Slegs indien ... = Only if ...
• betaal ons ... = do we pay ...

This is a fairly formal and clear way to express a condition.

Both can often be translated as if, but they are not always used in exactly the same way.

• indien is usually more formal or written
• as is more common in everyday speech

So:

• Slegs indien die bouplan gereed is ... sounds a bit more formal
• Net as die bouplan gereed is ... would sound less standard here and may not be the best equivalent for only if

A very natural less formal alternative would be:

• Slegs as die bouplan gereed is, betaal ons die aansoekfooi.

But indien fits especially well in administrative, legal, or official contexts.

This happens because indien die bouplan gereed is is a subordinate clause.

In Afrikaans, in many subordinate clauses introduced by words like indien, dat, omdat, and terwyl, the finite verb usually moves to the end.

So:

• main clause: Die bouplan is gereed.
• subordinate clause: indien die bouplan gereed is

That final is is a very important word-order feature in Afrikaans.

This is because the sentence begins with the conditional clause:

• Slegs indien die bouplan gereed is, ...

When a sentence starts with something other than the subject, Afrikaans usually puts the finite verb first in the main clause, before the subject. This is often called the V2 rule.

So the main clause becomes:

• betaal ons die aansoekfooi

rather than:

• ons betaal die aansoekfooi

Compare:

• Ons betaal die aansoekfooi.
• Môre betaal ons die aansoekfooi.
• Slegs indien die bouplan gereed is, betaal ons die aansoekfooi.

In each case, the verb comes early in the main clause.

Bouplan is a compound noun:

• bou = build / building
• plan = plan

Together, bouplan means building plan or construction plan.

Afrikaans, like Dutch and German, often writes compound nouns as one word. English sometimes writes similar expressions as two words, but Afrikaans usually joins them:

• bouplan
• aansoekfooi
• huisdeur
• skoolbus

So if you are an English speaker, it is useful to get used to Afrikaans combining nouns into one word.

Aansoekfooi is another compound noun:

• aansoek = application
• fooi = fee

So aansoekfooi means application fee.

Again, Afrikaans normally writes this as one word.

Each noun here has its own definite article:

• die bouplan = the building plan
• die aansoekfooi = the application fee

Afrikaans uses die as the definite article for all nouns, whether singular or plural, and regardless of grammatical gender. That makes it simpler than languages that have different forms like the masculine, the feminine, and so on.

So:

• die bouplan
• die planne
• die fooi
• die fooie

They all use die.

Yes, the comma is standard here.

The sentence begins with a subordinate clause:

• Slegs indien die bouplan gereed is,

and then moves to the main clause:

• betaal ons die aansoekfooi.

Afrikaans normally uses a comma to separate such an introductory subordinate clause from the main clause.

Yes. A common alternative is to put the main clause first:

• Ons betaal die aansoekfooi slegs indien die bouplan gereed is.

This means the same thing: We only pay the application fee if the building plan is ready.

Notice what changes:

• When the main clause comes first: Ons betaal ...
• When the subordinate clause comes first: ..., betaal ons ...

So the position of the clause affects the word order in the main clause.

No. Net can also mean only, and in everyday Afrikaans it is often more common.

So you may also hear:

• Net indien die bouplan gereed is, betaal ons die aansoekfooi.

However:

• slegs sounds more formal
• net sounds more conversational

Since this sentence sounds administrative or official, slegs is a very natural choice.

Usually, yes. Gereed commonly means ready or finished/prepared, depending on context.

Examples:

• Ek is gereed. = I am ready.
• Die kos is gereed. = The food is ready.
• Die bouplan is gereed. = The building plan is ready.

In this sentence, it means the building plan has been prepared and is ready for the next step.

It sounds somewhat formal and official.

That feeling comes from words like:

• slegs
• indien
• aansoekfooi

These are perfectly normal Afrikaans words, but together they sound like something you might read in:

• an application form
• a contract
• a municipal document
• an instruction sheet

In very casual conversation, someone might choose simpler wording, but this sentence is completely natural in formal written Afrikaans.