Do I need new refrigerant oil or desiccant when I install this?

You'll want fresh desiccant in your system during install — moisture degrades cooling performance. Whether you need new oil depends on how much you're flushing; your tech can assess that when pulling the old condenser.

Are there any hoses or fittings I need to buy separately?

This is the condenser unit only. If your existing hoses are in good shape, reuse them. If they're cracked or leaking, source replacement lines for your model year before you start the swap.

What tools do I need to get this in?

Standard hand tools — sockets, wrenches, and a refrigerant recovery system if you're handling the refrigerant yourself. Most shops recover and evacuate the system before removal, then recharge once the new condenser is mounted.