1) The availability of attractive financing. Plus, the spread between fixed-rate financing and actual year one cap rates is certainly the widest that it’s been in recent history, perhaps ever. (There’s rumor that there was a bigger spread during the Roman Empire, but that may just be an old wives’ tale.)
From a macro perspective, the spreads between the treasury indexes and the premium on multifamily interest rates will almost certainly widen in the near term, but cap rates should remain stable in Class-C properties. They will probably continue to compress to a certain degree for Class-B assets.