1. The deposit-before-you-see-it listing
A great apartment, a great price, and a "lister" who needs a deposit today to hold it, sent by wire or gift card, before you ever see the place or the person. The tell: urgency plus refusal to video-call or show the unit live. The defense: never send money before you've verified the person controls the actual apartment.
2. The overpayment refund
Your "subletter" sends a check for more than what's owed and asks you to refund the difference. The check bounces days later; your refund was real money. The tell: any payment larger than the agreed amount. The defense: a written payment schedule and refusing any transaction that isn't on it.
3. The vanishing subletter
Everything is friendly until October, when rent stops arriving and texts go unanswered, and with nothing signed, there is nothing to enforce and no evidence for anyone who could help. The defense: a signed agreement with a rent schedule, so a missed payment is a documented breach instead of an awkward conversation.
4. The unwritten side deal
A discount for mowing the lawn, a credit for the broken dryer, first month free "because you're a friend of a friend", agreed in a chat, remembered by exactly one of the two people involved. In practice, these small undocumented side deals may hurt students more often than dramatic scams do. The defense is boring: if it changes the money, it goes in the agreement.
5. The unapproved sublet
Everything between the two students is fine, but the landlord never consented, the lease prohibited subletting, and the subletter gets a knock on the door mid-semester. The original tenant is usually still on the hook. The defense: written landlord consent before anyone moves anything.