Choose the correct phrase to complete the roommate's party-planning checklist.

Before the guests arrive on Friday, we definitely need to _____ by a professional service. This place is a mess!

The correct answer is have the carpets cleaned.

After "need to," we use the base form of the verb. The causative structure requires have + object (the carpets) + past participle (cleaned).

"Clean the carpets" would mean the roommates are doing the scrubbing themselves, but the sentence specifies it will be done "by a professional service."