How do you actually verify a pallet supplier's load capacity claims before ordering in bulk

I am setting up a new storage facility for auto parts and every single supplier website I browse lists impressive sounding weight capacities but none of them explain how those numbers were actually tested, whether it is static load, dynamic load, or racked load, and honestly I do not have the engineering background to just eyeball a pallet and know if it will hold up under our specific stacking setup, a colleague who handles procurement for a bigger company told me to just ask for third party testing certificates and compare a few names before deciding, and when I mentioned I was struggling to narrow things down he brought up that his company has been working with a leading heavy duty pallets supplier in UAE for their last two facility expansions and never had a batch fail inspection, which was reassuring to hear but I still want to do my own homework rather than just go with a recommendation blindly, so if anyone here has gone through a similar vetting process I would appreciate knowing what questions actually mattered once the pallets were in real use and not just sitting in a spec sheet.