1998 Ford Windstar Transmission leak

My transmission is leaking major fluid at the trans cooler lines. These lines are metal and go into their own cooler box by the radiator. This is where it is leaking. Was quoted $400.00 to be fixed by a shop. Parts alone were $200. My question is can I have a mechanic do it outside a shop, without major problems and for less than 200 in labor.

Absolutely, an outside shop can handle cooler line replacement.