I'm confused by the question because your processes should be in place to pay your people no matter where they are.
That means you need to have registered as a foreign corporation wherever they are working, filed the W9s, W2s and 1099s so that they pay taxes correctly.
If you don't have a payroll processing company or an accountant (don't use ADP) to make sure you're perfectly covered then you should get one ASAP. There aren't too many faster ways to get shut down than to have a state or federal tax agency come hunting you down.
That means you need to have registered as a foreign corporation wherever they are working, filed the W9s, W2s and 1099s so that they pay taxes correctly.
If you don't have a payroll processing company or an accountant (don't use ADP) to make sure you're perfectly covered then you should get one ASAP. There aren't too many faster ways to get shut down than to have a state or federal tax agency come hunting you down.