Commercial Real Estate Conumdrum

What could happen if businesses decide not to rent high profile properties?  What if they go bust?  Would they put all their stuff in storage?  Well, you're somewhat covered here, as the Vanguard REIT ETF (VNQ) contains Public Storage (PSA) as one of the top three holdings.  For a patient investor with a more optimistic view of the American consumer, the reward is a dividend of almost 3.5%.  Hence the conundrum.