How to check the roll forming machine before the shipping

When checking, trust your eyes.  If problem, did not listen to the explanation from workers and engineers. Just tell them i need qualified roll forming machine.

My job is selling roll forming machine to my clients. and also supply qualified roll forming machines to clients. Because Ted supply after-sale service. If bad quality, i will be tired. So no machine shipping before solving all problems.

I can do this but what should client do. Send us balance payment timely.
Thanks.
Waiting is no good.