do it through the rental schedule section
as you enter info you should see a page that asks if the property was sold - so check that box
as you go through the pages you'll come to one with a link for sale of property. click the icon on that line.
this will allow you to enter the sales info.
if this is your first time using Turbotax it should allow you to enter the costs for the building and land and other assets. prior depreciation will need to be entered.
then you need to allocate the sales price and sales expenses among the various items. the IRS says you should allocate based on relative fair value, but any reasonable allocation method will probably produce the same results.