How can I move walls precisely using dimensions?
Temporary dimensions will display along the length of a wall as it is drawn, helping you draw walls to the desired length. Although dimensions display as you are drawing, you do not need to position walls precisely when you first draw them as they can be easily moved into place at any time.
, then in a clockwise fashion, click and drag out walls to create a basic structure.
Note: If you don't see temporary dimensions appear when a wall is selected, first make sure that they are enabled by navigating to View> Temporary Dimensions.

You can also change how temporary dimensions locate walls when they are selected. For example, you may want temporary dimensions to locate a wall's surface (Drywall) instead of a wall's dimension layer (Framing).
To control this in X17 and newer navigate to Edit> Default Settings> Dimension> Dimensions, click Edit, Edit your Currently Active Dimension Defaults, and on the Setup Temporary panel you can change how temporary dimensions locate your walls.
In X16 and prior, navigate to Edit> Default Settings, expand the Dimension category, select Temporary Dimensions, then click Edit to change how temporary dimensions locate walls.
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Numbers entered with an apostrophe denote feet and the numbers entered with quotes denote inches. If neither apostrophes nor quotes are included, the entered value defaults to inches.

Note: When resizing the exterior perimeter of a house using dimensions, it is important to work your way around the house in one direction. Relocate one wall at a time in succession so that you do not redefine the same dimensions more than once.
tool, and the various tools found by navigating to CAD> Dimensions 
Note: Auto Exterior Dimensions do not generate properly if there is a gap in exterior walls. For example, sometimes angled walls may not connect properly. If automatic dimensions do not generate, try selecting Build> Wall> Fix Wall Connections.
To generate interior dimensions automatically, click inside of a defined room to select it, then click the Auto Room Dimension edit tool.
, you are over a controlling dimension for the selected wall.