Intermittent Lights and Codes

I have a 2008 Prius with ~178k miles on it. I bought it fairly cheaply with ~165k miles on it. It has treated me well and no issues thus far. However, about 2 or 3 weeks ago, I was driving to a friends, and about 100 feet out, the red triangle and a lot of other lights pop up. I baby it into his driveway. I do some research and someone on here recommending checking the oil. I check the oil and it is lower than me (unbeknownst to me it has been burning oil). So, I do an oil change. I had lost my code reader so I was not able to reset the codes, so after a few hours of driving time, the lights all go away. The lights were off for about 3-5 days and then they come back on. So then I start to think this isn't just because of low oil. I check oil anyway and the oil is fine. I get the car home and on my way home, the lights go off. When I got home, I ordered another OBD2 reader (Blue Driver) to replace the one I lost. So while I was waiting on the reader to get to me through the mail, I have to keep driving it because it is my only mode of transit. The lights came and went at an unpredictable interval and pattern. So when I got the OBD2 reader in the mail, the lights came on the next day. So, I scan it, and get codes P0AFA (hybrid system voltage low) and P3000. I have looked on here and on other places and theories and fixes are all over the place. I have read a lot of places that if it truly is the battery the lights would stay on all the time.

So, does anyone have any ideas on what I should do next or how to proceed?
Much appreciated.

 

Thank you for that! I am not opposed to doing some DIY digging of my own. I am looking into getting a reader compatible with Dr. Prius so I can get the INF codes. I am new to the Prius world, so where would I find the HV Battery ECU?