Have you ever noticed that the more number of people you go with the more likely you are to succeed in renting the place? You go in with a family of two kids and it is almost assured that the apartment is yours. You go with one kid less, its still likely if you happen. To be someone single it's going to be a herculean task and if you happen to be single in your young twenties, then you are already branded as a drug dealer, runaway, or even worse, a pimp.
Because this is the reaction you get from the landlords when you go to inquire about that specific apartment that they have willingly decided to rent out. Judgments are made even before the first word is even uttered. This trend is also very extensively been followed down south where houses for rent in Kerala have a very similar thought process when it comes to renting out apartments.