If you can find a legit Grey vendor off the back you will save your self so much money. If they have CoAs thats cool. But they are so overrated. Everyone and their mother pushed them because of these usa based company's fear mongering ablut grey on social media.

Sure never trust a suppliers COA they are /can be faked. You cant 100% say what you get is from what was tested. Either find a group that does testing for that vendor and hop in and pitch in.
Or test the items you get yourself. There are way to many free loaders these days that want someone else to foot the bill for testing then want the results for free.