Buying LED displays from china - need guidance!

Hello everyone!

I'm looking to buy some LED outdoor screens from China .

Been doing some research and the big players in China are Absen, Unilumen, Leyard, Retop to name a few.

What should I be looking for if i was considering buying one for outdoor display screens?

What factors do i need to consider (i.e led bulbs, IC or etc.)?

Anyone experienced or know anything about China companies who manufacture LEDS?

I found one b2b marketplace en.ofweek.com , the LED manufacturers credible?

Thanks a bunch.

Regards

Commercial use or personal.
WHat size of display?