"I have no clue what you are talking about. There are no tax breaks for keeping space unrented. There is no logic in keeping a space unrented. Landlords want more rent, not no rent. What disincentivizes lower rents is greed, not taxes."
Perhaps we have a miscommunication here, but what you wrote flies in the face of everything we have read that has gotten SO much publicity lately, with FINALLY a move to eliminate such tax breaks. Without getting too far off topic, can you please explain what you mean?
To clarify: Just because some landlords keep properties unrented for tax breaks doesn't mean ALL of them do. A lot of landlords throw out tenants when their leases are up in order to get other tenants who can afford to pay higher rents.