Bevor wir den Mietvertrag unterschreiben, möchten wir die Wohnung noch einmal besichtigen.

Because bevor introduces a subordinate clause. In German, the conjugated verb in a subordinate clause usually goes to the end.

So:

• Bevor wir den Mietvertrag unterschreiben = Before we sign the rental contract

Here, unterschreiben is the conjugated verb, and it moves to the end because of bevor.

Because the sentence starts with the subordinate clause:

• Bevor wir den Mietvertrag unterschreiben, ...

When a subordinate clause comes first in German, the main clause still follows the normal rule that the conjugated verb must be in position 2. Since the first position is already taken by the whole bevor clause, the verb comes next:

• möchten wir die Wohnung noch einmal besichtigen

So this is normal German word order, not a special exception.

A rough structure is:

1. Bevor wir den Mietvertrag unterschreiben
2. möchten
3. wir die Wohnung noch einmal besichtigen

Bevor means before in the sense of before something happens. It introduces a clause with its own subject and verb.

Examples:

• Bevor wir gehen, essen wir noch etwas. = Before we leave, we’ll eat something first.
• Bevor ich antworte, denke ich nach. = Before I answer, I think about it.

So in your sentence, bevor sets up the action that happens earlier than the main action.

Because Mietvertrag is the direct object of unterschreiben, and that means it takes the accusative case.

• nominative: der Mietvertrag
• accusative: den Mietvertrag

Since Mietvertrag is masculine, its article changes from der to den in the accusative.

Compare:

• Der Mietvertrag ist lang.
  The rental contract is long.
  → subject, so nominative

• Wir unterschreiben den Mietvertrag.
  We sign the rental contract.
  → direct object, so accusative

Wohnung is feminine, and for feminine nouns, the article does not change between nominative and accusative.

• nominative: die Wohnung
• accusative: die Wohnung

So even though die Wohnung is the direct object of besichtigen, it still stays die.

Compare:

• Die Wohnung ist schön.
• Wir besichtigen die Wohnung.

Same article, different grammatical role.

Because möchten works like a modal verb here. It expresses what someone would like or want to do, and the other verb stays in the infinitive at the end of the clause.

So:

• wir möchten ... besichtigen = we would like to view/inspect

This is a very common German pattern:

• Ich möchte schlafen.
• Wir möchten essen.
• Sie möchte die Stadt besichtigen.

The conjugated verb is möchten, and the main action appears as an infinitive at the end: besichtigen.

Because after modal verbs like möchten, können, wollen, müssen, dürfen, and sollen, German uses the infinitive without zu.

So you say:

• Wir möchten die Wohnung besichtigen.

Not:

• Wir möchten die Wohnung zu besichtigen. ❌

Examples:

• Ich kann kommen.
• Sie will lernen.
• Wir müssen gehen.

Möchten usually means would like to. It is softer and more polite than wollen, which is more direct and usually means want to.

So:

• Wir möchten die Wohnung noch einmal besichtigen. = We would like to view the apartment once more.

If you said:

• Wir wollen die Wohnung noch einmal besichtigen.

that would sound more forceful: We want to view the apartment again.

In many everyday situations, especially polite ones, möchten is the more natural choice.

Noch einmal means once again, one more time, or simply again.

So:

• die Wohnung noch einmal besichtigen = to view the apartment again / one more time

It suggests that they have probably already seen the apartment and want another viewing before signing.

In everyday speech, people often say:

• nochmal

which is a shorter, more conversational version of noch einmal.

So these are very close:

• noch einmal
• nochmal

Yes, German word order is flexible, but some positions sound more natural than others.

Here:

• möchten wir die Wohnung noch einmal besichtigen

is very natural.

Noch einmal usually appears before the infinitive or near the part it modifies. Since it describes the action besichtigen, putting it before besichtigen works well.

You may also hear:

• möchten wir noch einmal die Wohnung besichtigen

This is also possible, though the version in your sentence is very natural and smooth.

Besichtigen means something like to inspect, to view, or to look at officially/in person, especially for places, buildings, apartments, tourist sights, and similar things.

In this sentence, it is a very natural verb for viewing an apartment before renting it.

Comparison:

• besichtigen
  to inspect/view formally or purposefully
  very common for apartments, houses, museums, landmarks

• besuchen
  to visit
  more for people, places, events, cities, etc.

• ansehen
  to look at/watch
  broader and less formal

For apartment hunting, eine Wohnung besichtigen is the standard expression.

Because German often forms compound nouns by joining smaller nouns into one word.

Here:

• Miete = rent
• Vertrag = contract

Together:

• Mietvertrag = rental contract / lease agreement

This is extremely common in German. The last part usually determines the basic meaning and grammatical gender. Since Vertrag is masculine (der Vertrag), der Mietvertrag is also masculine.

Because the sentence begins with a subordinate clause, and in German, subordinate clauses are separated from the main clause by a comma.

So:

• Bevor wir den Mietvertrag unterschreiben, möchten wir ...

This comma is required in standard German spelling.

Yes. You could also say:

• Wir möchten die Wohnung noch einmal besichtigen, bevor wir den Mietvertrag unterschreiben.

This means the same thing.

The difference is mostly about emphasis and style:

• starting with Bevor ... emphasizes the time condition first
• starting with Wir möchten ... emphasizes what we want to do

Both are natural.

It has two parts:

1. Subordinate clause introduced by bevor

   • Bevor wir den Mietvertrag unterschreiben

2. Main clause

   • möchten wir die Wohnung noch einmal besichtigen

So the full structure is:

• Bevor
  • subject + object + verb
• comma
• finite verb + subject + object + adverbial expression + infinitive

This is a very typical German pattern: subordinate clause first, then main clause with inversion.

Yes. Each clause needs its own subject unless it is omitted for a special reason, which is not the case here.

So German says:

• Bevor wir den Mietvertrag unterschreiben, möchten wir ...

Even though English also repeats we, learners sometimes wonder whether German can drop it. In this sentence, it cannot.

Each clause is complete:

• wir unterschreiben
• wir möchten

The dictionary forms are:

• unterschreiben = to sign
• möchten is a special form related to mögen, but learners usually treat möchten as its own useful form meaning would like
• besichtigen = to inspect/view

In the sentence:

• unterschreiben is conjugated for wir
• möchten is conjugated for wir
• besichtigen stays in the infinitive because it goes with möchten

It sounds neutral to slightly formal, which fits the context well.

Reasons:

• Mietvertrag is a formal/legal word
• besichtigen is a standard and appropriate verb for apartment viewings
• möchten sounds polite and natural

So this is exactly the kind of sentence you might actually use in a real housing situation.