fánshì yǒu yùfùkuǎn de kèrén, dōu kěyǐ ná fángkǎ.

It is a very common pattern meaning whenever / any / all those who meet a certain condition, then....

So:

• 凡是有预付款的客人，都可以拿房卡。

follows this structure:

• 凡是 + [condition/category]，都 + [result/rule]

In this sentence:

• 凡是有预付款的客人 = any guests who have made a prepayment
• 都可以拿房卡 = all of them may get a room card

This pattern is often used in rules, notices, policies, and general statements.

Both can relate to all, but they are not exactly the same.

• 凡是 is often used to mean anyone/anything that fits a condition
• 所有 means all in a more direct, inventory-like sense

Compare:

• 凡是有预付款的客人，都可以拿房卡。
  = Any guest who has a prepayment may get a room card.

• 所有有预付款的客人都可以拿房卡。
  = All guests with a prepayment may get a room card.

Both are understandable, but 凡是……都…… sounds especially natural for a rule or policy.

Because 有预付款 is modifying 客人.

In Mandarin, when a phrase describes a noun, you usually put 的 between the describing phrase and the noun:

• 有预付款的客人 = guests who have a prepayment
• 会说中文的人 = people who can speak Chinese
• 穿红衣服的女孩 = the girl wearing red clothes

So here:

• 有预付款 = have a prepayment
• 的客人 = guests who...

Without 的, the phrase would be ungrammatical.

Both are possible, but they focus on slightly different things.

• 有预付款的客人 focuses on the state/status: the guest has a prepayment on record
• 付了预付款的客人 focuses on the action: the guest paid the prepayment

In a hotel, notice, or front-desk context, 有预付款 can sound a bit more administrative, as if the system shows that a prepayment exists.

So:

• 有预付款的客人 = guests with prepayment
• 付了预付款的客人 = guests who paid the prepayment

Both are natural, but the original sentence sounds like a policy statement.

预付款 means prepayment or advance payment.

It refers to money paid before the main service is fully provided. In a hotel context, it usually means the guest has already paid some amount in advance.

A learner may wonder whether it means deposit. Sometimes the English translation in real life might become deposit, but strictly speaking:

• 预付款 = advance payment / prepayment
• 押金 = deposit, especially a refundable security deposit

So they are related, but not identical.

With 凡是, 都 is very commonly used and often expected.

The pattern is:

• 凡是……都……

Here, 都 marks that the rule applies to all cases that fit the condition.

So:

• 凡是有预付款的客人，都可以拿房卡。

sounds complete and natural.

If you remove 都:

• 凡是有预付款的客人，可以拿房卡。

it may still be understandable, but it sounds less standard and less polished. For learners, it is best to remember 凡是……都…… as a set pattern.

Here it mainly expresses permission / eligibility, not physical ability.

So 可以拿房卡 means:

• may get the room card
• are allowed to take the room card
• are eligible to receive the room card

It does not mainly mean that they are physically capable of picking it up.

In many real-world notices, 可以 often means may / can according to the rules.

Yes, 拿 literally means take / hold / get, but in context it often means something like:

• pick up
• get
• receive

So 拿房卡 in a hotel setting can naturally mean get the room card from the front desk.

Other possible verbs would give slightly different tones:

• 拿房卡 = everyday, conversational
• 领房卡 = more formal, like receiving something issued
• 取房卡 = collect/pick up
• 拿到房卡 = successfully obtain the room card

The original sentence uses a simple, natural spoken-style verb.

In this context, 客人 most naturally means guest.

More generally, 客人 can mean:

• guest
• customer
• visitor

The exact meaning depends on the setting.

In a hotel sentence with 房卡, English speakers would usually understand 客人 as hotel guests.

So although 客人 is broad in Chinese, the context makes guest the most natural translation here.

A helpful way to see it is in two big parts:

• 凡是有预付款的客人
  = as for any guests who have a prepayment

• 都可以拿房卡
  = all may get a room card

So the whole sentence is basically:

• [group defined by a condition] + [rule that applies to that whole group]

Also notice that Mandarin places the modifying phrase before the noun:

• 有预付款的客人
  literally: have-prepayment de guests

This is normal in Chinese, even though English usually puts the relative clause after the noun:

• guests who have a prepayment

Mandarin nouns usually do not change form for singular vs. plural.

So 客人 can mean:

• guest
• guests

The sentence is understood as referring to a whole category, and 都 strongly suggests a plural or collective meaning:

• all guests who fit this condition

So even though 客人 itself does not have a plural ending like English -s, the sentence clearly refers to the whole group.

Yes. The original sentence is natural, but it sounds a bit like a rule or notice. More conversational alternatives might be:

• 付了预付款的客人都可以拿房卡。
• 有预付款的话，就可以拿房卡。
• 只要付了预付款，就可以拿房卡。

These are slightly different in tone:

• 凡是……都…… = policy-like, formal, rule-based
• 只要……就…… = as long as...
• 有……的话 = if there is / if you have...

So the original is perfectly good, especially for hotel policy language.

The comma separates the condition/group from the main statement.

• 凡是有预付款的客人， = as for any guests with prepayment,
• 都可以拿房卡。 = they may all get a room card.

In writing, this comma helps the sentence read more clearly, especially because the first part is fairly long and functions like a topic or condition.

It is not always absolutely required in every short sentence, but here it is very natural and helpful.