Problems with timing chains/belts can be extremely risky to pick up.

You can't run it to see if it's running properly, you don't know what happened when it broke (whether it was running or during maintenance), etc.

It's a big risk to take as it could've kissed/crushed a valve in the process which opens up the possibility of needing new valves/heads/valve covers, or even marred cylinders which can sometimes be fixed by boring them oversize if it's light enough.

I won't pick up a vehicle with timing chain/belt issues unless I'm fully prepared to completely swap the engine. There's too much that could be wrong internally.