Dear Bhumika, your question is worded incorrectly. What you should be asking hosts is: "What are your Top 3 Essential House Rules" that you want Airbnb to make sure that guests abide by?"
Hosts are typically not in a position to make guests abide by rules.
Guest smoking in the bedroom?
Guest eating smelly food in the bedroom and leaving greasy stains on bedding and upholstery?
Guest brings additional people / pets who are not paid for?
Guest blocking the bathroom sink with food, blocking toilet with wet wipes, etc?
Guest breaking shower, burning tabletop, causing other damage?
Guests having rowdy drunken party in their room, keeping us and other guests awake.
I've had all these things happen due to Airbnb guests, and was: a) unable to stop these things hapening, even though these are expressly forbidden by my house rules, and b) unable to get fair compensation from the guest or Airbnb.
For example in the case of the guest who brought an additional person, I never received a payment from the guest, nor did I receive any compensation from airbnb.
In the case of the guests who broke my shower, guests refused to pay and I received no compensation from airbnb.
In the case of the drug addict guest who left the room so filthy and stinky that I had to clean not just the bedding but the duvet, pillows, mattress and pillow protectors, sofa upholstery and curtains. The guest refused to pay and Airbnb gave me the princely sum of £30 as a "goodwill" gesture to compensate for all the additional cleaning, even though I provided evidence of commercial cleaning costs. Airbnb CS told me that because I had gone ahead and got the items cleaned before getting Airbnb's OK, I was not covered.
What Airbnb need to do is this:
1) Let each host identify their top 3 rules for each of their listings.
2) When a guest wants to make a reservation, BEFORE the reservation is confirmed, show the guest those top 3 rules, and get them to explicitly agree to them.
3) Implicit rules such as max. number of guests, ages of guests, no pets, no parties, no smoking, etc. must also be explicitly agreed to by the guest.
4) Only if the guest agrees to the implicit rules and the host's top 3 rules, can the reservation be confirmed.
5) Lastly, Airbnb needs to support hosts when guests break these rules.