How to test a second hand Vive Pro 2?

[Breeze23]

Hey all,
Im new to the VR scene, though ive been lurking in the background hoping to find a second hand Vive Pro 2 for quite some time. I recently found a used headset only kit and am hoping to get some advice as to how to test the unit prior to commiting to buying it. Chances are i wont be able to hook it up to a pc, and i was wondering if there were any tips in regards to testing or ensuring it works if i were to meet the person offering the unit? 

Any suggestions would be helpful, and i hope to be racing via Forza or playing Alyx real soon.

Thanks,
Breeze