The key difference between creating a budget using Realogic Budget and creating a long term forecast in LTF is the use weighted averages speculative deals (also known as at rollover).
In Realogic Budget, there is no notion of an automatically created tenant. In long term forecasting, this concept becomes helpful in smoothing out expectations for tenancy beyond the short term.
The Difference between Realogic Budget and Realogic LTF
While not ideal in a short term budget (tenant improvements, downtime and leasing commissions become overly simplified where more accurate predictions are expected and possible), the concept of weighted average at rollover allows a smoothing out of expectations that can be applied for realistic long term forecasts.