At the bottom of the list of assets is a button labeled "Add an Asset". This will lead you to questions that place the asset in a class, etc.....
SELECT "OTHER ASSET" type to customize years, class, method, etc. manually.
I would recommend entering the start date as the date the property was transferred to the LLC or whenever the LLC started managing the property or otherwise started conducting business operations.
Note: If you're using the desktop software you also have the option to go to forms, got to the schedule E worksheets for the property, click on depreciation, click the magnifying glass to the left, and "create a new copy" to add an asset worksheet for an asset not yet listed. This is especially useful if you are moving to TurboTax and have a list of assets already in service to enter, as you describe.
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