is it worth repairing a 2012 macbook pro?

I have a 2012 MacBook pro that was stored for 2 years and I booted it back up and it starting having power issues. I replaced the battery and that fixed it. Then it began a loop from the login of the device to a loading bar that then stopped midway and rebooted. It was a loop. I callled apple and got some great help that involved rebooting it into safe mode to at first try to reset it to Lion OS and that failed. The screen would go black with blue vertical lines across the screen. We tried rebooting in safe mode to reset it to the last version of Sierra which it had before it tanked. It also gave the same result black screen w blue lines. The support employee said to take it to a local apple repair shop, not an apple store since this was too old for apple to repair. The reviews Ive read for the repair shops they gave me are not good so I am wondering to either try and make repairs myself of buy a replacement.

Anyone ran into an issue like this and solved it with repairs?