At least in Manhattan, no one will give you a contract for more than a year - they will want to renegotiate in a year and demand is high enough to not worry about having no tenants. In Europe multi-year contracts are somewhat typical, but never heard of that in NYC. Similarly, very few will do a contract for less than a year. So the one-time broker fee gets amortized over 12 months, but the net effect is a wealth transfer from long-term tenants to landlords (because they continue paying that increase in perpetuity).