1) Yes, TurboTax will give you Form 2210.
2) They are asking about being physically in the office to run your business. For example, if you were a salesman who made visits to clients, you would not be using the office at that time. You put whatever the actual percentage is.
3) If you are not going to continue your business do not take a Section 179 expense. You can use MACRS and depreciate them over their 5-year useful lives. That way, if the business folds, you do not have to recapture depreciation.
