I am looking at buying 1987 W124 300D Turbo with a clean body but it won't start . - No black smoke when trying to start . I disconnected the pipe between the turbo and intake manifold and it almost started, lots of black smoke coming out of the turbo and engine almost started - bad turbo ?

How much is used or rebuilt turbo ?
Can I bypass or shunt the turbo with a pipe and make the car a non-turbo .

How do I check for a cracked head besides looking for oil in the coolant and coolant in the oil (remember it doesn't run) ?

I also need more info on how to check out the EGR and Trap Oxidizer stuff ( any photos or drawings ? )

What else should I look for on this car .

-Thanks. ...................... Edited title/text per PM request.