MacBook that works fine but sometimes black screen appear

Hi guys,

Not sure if this topic is appropriate here, I have a MacBook (retina, 12" early 2015) model that works fine but sometimes black screen appears while the macbook is running (even if I attach it to an external monitor). I bought it about 1.5 years ago and it is already out of warranty and so I didn't bother bring it to apple for repair. I am not a tech savy person, have no idea how to fix it and thinking to just let it go by selling the parts or the whole macbook because it is still working fine. How do you think I should go about selling this laptop and how much would people recommend?

Here are the specs for the macbook.

512 GB PCle-based onboard flash storage

1.2GHz dual-core, Intel core M5 processor Turbo Boost up to 2.7GHz

8GB memory

Intel HD Graphics 515

Battery less than 50 counts and with normal condition

With minor cosmetic defects (dents on the edges)

Japanese keyboard

LCD display working fine with no issue

Trackpad and keyboard clean and working perfectly including backlights

Fans working smoothly

Thanks in advance and greatly appreciate if anyone could give me an advice on how to sell this laptop!

P.S not sure why my post got deleted. Thus a new post here.