Use the ResizeUnitScale and ResizeUnitCount properties to specify a different resizing units. If these properties are not used, the UnitScale property indicates the resizing time units. For instance, using  the ResizeUnitScale and ResizeUnitCount properties you can let the user resizing the bars up to hours even if the chart displays days. Use the ResizeUnitScale and ResizeUnitCount properties to refine the way how the user resizes or creates new bars. The InsideUnit property specifies the time scale unit being used to paint the inside zoom units.

Your application can provide some options to help user while performing moving or resizing the bars at runtime as follow:

• grid lines, that can be shown only when moving or resizing, using the ChartStartChanging and ChartEndChanging events
• select date, to specify the margins of the area you want to highlight
• ticker, that shows the cursor's position in the chart, or while resizing, it shows the size and the position of the bar 
• ability to specify a resizing/moving unit, different that the displayed one ie while the chart displays days, you can specify the resizing unit on hours.
• inside zoom, that can be used to magnify the portion of the chart being selected