Smoking at start up

The most likely cause of that if it only happens on the initial start, is leaking valve stem seals. When the engine is off some of the oil in the cylinder head is going past the seal and into the combustion chamber. Then when you start the engine it burns off and creates the smoke. Replacing the seals can be done however it requires quite a bit of engine teardown to get to them. The camshafts and valve lifters have to be removed and then each cylinder get's done in turn. There are a couple options, take it apart and replace the seals or what would likely end up being cheaper and faster would be to get a remanufactured cylinder head and swap that. That would give you new seals but also replace the head gasket and other gaskets and while it was apart you could replace the timing chain and guides. Or if the vehicle is in very good condition you could even opt to replace the entire engine. However that is a very costly thing on an 11 year old vehicle. Personally if it were mine I'd probably try one of the additives that claims to help stop the oil burning and see if it worked.